PROSPECTUS





                           THERMO ELECTRON CORPORATION

                         276,348 SHARES OF COMMON STOCK


We are  registering  up to 276,348  shares of our  common  stock for sale by the
Selling  Stockholders  listed on page 8 of this  prospectus.  These  shares  are
issuable  upon  conversion  of  warrants  that we assumed in our merger with our
former majority-owned subsidiary Thermo TerraTech Inc.

We will receive the  exercise  price for the warrants in the event that they are
exercised by the warrantholders.

Our  common  stock is traded on the New York  Stock  Exchange  under the  symbol
"TMO." On April 30,  2001,  the closing  sale price of one share of common stock
was $26.36.

Our  address  is  Thermo  Electron  Corporation,   81  Wyman  Street,   Waltham,
Massachusetts 02454-9046, and our telephone number is (781) 622-1000.


                 This Investment Involves A High Degree of Risk.
  You Should Purchase These Securities Only If You Can Afford A Complete Loss.
                     See "Risk Factors" Beginning on Page 2.


Neither  the  Securities  and  Exchange  Commission  nor  any  state  securities
commission  has approved or disapproved  of these  securities,  or determined if
this prospectus is truthful or complete. Any representation to the contrary is a
criminal offense.





                                  May 10, 2001







                           THERMO ELECTRON'S BUSINESS

     Thermo Electron  Corporation  (also referred to in this document as "Thermo
Electron,"  "we," or "the  company")  is a  global  leader  in the  development,
manufacture,  and sale of technology-based  instrument systems,  components, and
solutions used in virtually every industry to monitor, collect, and analyze data
to  provide  knowledge  for  the  user.  For  example,   our  powerful  analysis
technologies help biotech  researchers sift through data to make the discoveries
that will fight  disease  or prolong  life;  allow  telecommunication  equipment
manufacturers to fabricate components required to increase the speed and quality
of  communications;  and  monitor and control  industrial  processes  on-line to
ensure that critical quality standards are met efficiently and safely.

     In the late 1980s, we adopted a strategy of spinning out certain businesses
into separate  public  subsidiaries  in which we kept a majority  ownership.  By
1997, we had spun out 22 public entities serving many diverse markets.

     In 1998,  we began to  reorganize  and  simplify  our  structure  to regain
business focus. During 1999, three of our public subsidiaries were taken private
and  then a fourth  in  early  2000.  In  January  2000,  we  announced  a major
reorganization that would allow us to focus solely on our instruments  business.
As part of this plan, we took private all of our remaining public  subsidiaries,
other than Spectra-Physics  Lasers, Inc.  (Spectra-Physics or SPLI), in which we
acquired a majority  interest in 1999 and  continue  to own 78  percent;  Thermo
Fibertek  Inc. and its Thermo  Fibergen  Inc.  subsidiary,  which are  discussed
below;  and  Thermo  Cardiosystems  Inc.,  which we sold in  February  2001.  In
addition,  we decided to sell noncore businesses with aggregate revenues of more
than $1 billion.  We also expect to issue as a dividend to our  shareholders two
businesses that we plan to spin-off completely:

     -    one business  serves the  healthcare  industry with a range of medical
          products for diagnosis and monitoring;

     -    the other,  Thermo Fibertek,  supplies systems to the paper making and
          recycling industry, as well as fiber-based consumer products.

     In  February  2001,  the  company  announced  that  it had  entered  into a
definitive agreement to sell its power generation business.

     Our strategy  going  forward is to emphasize  internal  growth by investing
proceeds  from the sale of  noncore  businesses  to pursue  developments  in the
high-growth  markets  that we serve,  particularly  life  sciences  and  optical
technologies.  We also plan to  augment  that  growth  by  making  complementary
acquisitions.

     Thermo Electron is a Delaware corporation and was incorporated in 1956. The
company  completed its initial public offering in 1967 and was listed on the New
York Stock Exchange in 1980. Its principal  executive  offices are located at 81
Wyman Street,  Waltham,  Massachusetts  02454-9046,  and its telephone number is
(781) 622-1000.






                                  RISK FACTORS

     Investing in our common  stock is very risky.  You should be able to bear a
complete  loss of your  investment.  This  prospectus,  including  the documents
incorporated  by reference,  contains  forward-looking  statements  that involve
risks or  uncertainties.  Actual  events or results may differ  materially  from
those  discussed  in  this  prospectus  and in  the  documents  incorporated  by
reference.  Factors that could cause or contribute to such differences  include,
but are not limited to, the factors  discussed  below as well as those discussed
elsewhere in this prospectus and in the documents incorporated by reference.

     Thermo  Electron faces a number of challenges in integrating its instrument
businesses.

     Thermo Electron has historically operated its instrument businesses largely
as autonomous,  unaffiliated operations.  As part of its reorganization,  Thermo
Electron has begun to manage these operations in a more coordinated  manner. The
following   factors  may  make  it  difficult  to  successfully   integrate  and
consolidate Thermo Electron's instrument operations:

     -Thermo  Electron's  success in integrating these businesses will depend on
its ability to coordinate  geographically  separate  organizations and integrate
personnel with different business backgrounds and corporate cultures.

     -Thermo  Electron's  ability  to  combine  these  businesses  will  require
coordination  of  previously  autonomous  administrative,  sales and  marketing,
distribution, and accounting and finance functions and expansion and integration
of information and management systems.

     -The  integration  process  could become  disruptive  to Thermo  Electron's
instrument businesses.

     Moreover,  Thermo  Electron  may  not be able to  realize  all of the  cost
savings  and other  benefits  that it  expects  to result  from the  integration
process, even if the process is completed.

     It may be  difficult  for Thermo  Electron  to expand  because  some of the
markets for its products are not growing.

     Some of the markets in which  Thermo  Electron  competes  have been flat or
declining over the past several years. To address this issue, Thermo Electron is
pursuing a number of strategies to improve its internal growth, including:

     - finding new markets for its products,  including, most significantly,  in
the areas of proteomics and photonics;

     - developing new applications for its technologies;

     -  combining  sales and  marketing  operations  in  appropriate  markets to
compete more effectively;

     - actively funding research and development; and

     - strengthening its presence in selected geographic markets.

     Thermo Electron may not be able to successfully implement these strategies,
and these strategies may not result in growth of Thermo Electron's business.

     The proposed  spinoffs of Thermo  Fibertek and the business that serves the
healthcare  industry  may not  result in  companies  with  strong  liquidity  or
financial performance.

     The  completion  of the spinoffs of Thermo  Fibertek and the business  that
serves the healthcare  industry with a range of medical products for diagnostics
and  monitoring  is subject to final  action by the board of directors of Thermo
Electron.  In addition,  Thermo  Electron has chosen to delay the spinoffs until
the second half of 2001,  as a result of the current  weakness in the  financial
markets, in order to maximize shareholder value.

                                       2


     Thermo Electron is unable to predict the liquidity or market performance of
the shares of the businesses it plans to spin off.  Although Thermo Fibertek has
publicly  traded  shares,  the  historic  prices  of  these  shares  may  not be
representative  of the trading price of Thermo Fibertek's common stock after the
number of shares held by its stockholders  other than Thermo Electron  increases
as a result of the spinoff.  There is currently no public trading market for the
shares of the company  that  conducts the  business  that serves the  healthcare
industry.  The businesses  that Thermo Electron is spinning off may not have the
financial  resources and management  skills  necessary to succeed as independent
entities.

     As a result of the spin-off of Thermo Fibertek, Thermo Electron will remain
as the guarantor of  indebtedness  issued by Thermo  Fibertek even though Thermo
Electron will no longer control Thermo Fibertek's business or operations.

     Thermo  Electron has  guaranteed  the payment of principal  and interest on
$153 million principal amount of debentures issued by Thermo Fibertek Inc. These
debentures  mature  in July  2004.  Thermo  Electron  will  remain  liable  as a
guarantor for this obligation following the spinoff,  although it will no longer
control the business or operations of Thermo Fibertek.

     Thermo Electron has significant international operations,  which entail the
risk that  exchange  rate  fluctuations  may  negatively  affect  demand for its
products and its profitability.

     International   revenues  account  for  a  substantial  portion  of  Thermo
Electron's  revenues,  and Thermo  Electron  intends to continue  expanding  its
presence in international  markets.  In 2000,  Thermo  Electron's  international
revenues from continuing  operations,  including export revenues from the United
States,  accounted for  approximately  50% of its total revenues.  International
revenues  are subject to the risk that changes in exchange  rates may  adversely
affect  product  demand and the  profitability  in U.S.  dollars of products and
services  provided by Thermo  Electron  in foreign  markets,  where  payment for
Thermo  Electron's  products  and  services is made in the local  currency.  For
example,  in fiscal  2000,  the  unfavorable  effects  of  currency  translation
decreased revenues of Thermo Electron's continuing operations by $80.0 million.

     Thermo Electron has acquired several companies and businesses;  as a result
it has  recorded  significant  goodwill  on its  balance  sheet,  which  it must
continually evaluate for potential impairment.

     Thermo  Electron  has acquired  significant  intangible  assets,  including
approximately $1.4 billion of goodwill that it has recorded on its balance sheet
as of December 30, 2000.  Thermo  Electron  amortizes this goodwill  principally
over 40 year  periods.  Thermo  Electron  assesses the future useful life of the
goodwill  it has on its  books  whenever  events  or  changes  in  circumstances
indicate  that  the  current  useful  life  has  diminished.   These  events  or
circumstances  generally  include  operating losses or a significant  decline in
earnings associated with the acquired business or asset.  Goodwill  amortization
from Thermo  Electron's  continuing  operations  was $38 million in fiscal 2000.
Thermo  Electron's  ability to  realize  the value of the  goodwill  that it has
recorded  as a  result  of its  acquisition  of the  minority  interests  in its
formerly  publicly-traded  subsidiaries  will depend on the future cash flows of
these  businesses.  These cash flows in turn  depend in part on how well  Thermo
Electron has integrated these businesses.

     Thermo  Electron must develop new products,  adapt to rapid and significant
technological  change,  and respond to introductions of new products in order to
remain competitive.

     Thermo Electron's growth strategy  includes  significant  investment in and
expenditures for product development,  including most significantly in the areas
of proteomics and photonics. Thermo Electron intends to increase spending in the
area of research and development.  Thermo Electron sells its products in several
industries  that  are  characterized  by  rapid  and  significant  technological
changes,  frequent new product and service  introductions  and  enhancements and
evolving industry  standards.  Without the timely  introduction of new products,
services and enhancements,  Thermo Electron's  products and services will likely
become  technologically  obsolete  over  time,  in which  case its  revenue  and
operating results would suffer.

                                       3


     Thermo Electron's  customers use many of its products to develop,  test and
manufacture  their own products.  As a result,  Thermo  Electron must anticipate
industry trends and develop products in advance of the  commercialization of its
customers' products.  If it fails to adequately predict its customers' needs and
future   activities,   Thermo  Electron  may  invest  heavily  in  research  and
development of products and services that do not lead to significant revenue.

     Many of its products and products  under  development  are  technologically
innovative and require significant planning, design, development, and testing at
the technological,  product, and manufacturing-process  levels. These activities
require Thermo Electron to make significant investments.

     Products  in  Thermo  Electron's  markets  undergo  rapid  and  significant
technological  change  because of quickly  changing  industry  standards and the
introduction of new products and  technologies  that make existing  products and
technologies  uncompetitive or obsolete. Thermo Electron's competitors may adapt
more quickly to new  technologies  and changes in customers'  requirements  than
Thermo Electron can. The products Thermo  Electron is currently  developing,  or
those it will  develop in the  future,  may not be  technologically  feasible or
accepted by the  marketplace,  and its  products or  technologies  could  become
uncompetitive or obsolete.

     Thermo  Electron  sells its  products and services to a number of companies
that operate in cyclical industries, which could adversely affect its results of
operations when those industries experience a downturn.

      The growth and profitability of Thermo Electron's Optical Technologies
segment depends in part on sales to the semiconductor and telecommunications
industries, which are subject to cyclical downturns. These industries have begun
to experience slowing trends. A prolonged slowdown in these industries would
adversely affect sales by the Optical Technologies segment, which in turn could
adversely affect Thermo Electron's revenues and results of operations.

     Changes in governmental regulations may reduce demand for Thermo Electron's
products or increase its expenses.

     Thermo Electron competes in many markets in which it and its customers must
comply  with  federal,   state,   local,  and  foreign   regulations,   such  as
environmental, health and safety, and food and drug regulations. Thermo Electron
develops, configures, and markets its products to meet customer needs created by
those regulations. Any significant change in regulations could reduce demand for
Thermo Electron's products.  For example, many of Thermo Electron's  instruments
are  marketed  to  the  pharmaceutical  industry  for  use  in  discovering  and
developing drugs.  Changes in the Food and Drug  Administration's  regulation of
the drug discovery and  development  process could have an adverse effect on the
demand for these products.

     Demand for some of Thermo  Electron's  products depends on capital spending
policies of its customers and on government funding policies.

     Thermo  Electron's  customers include  manufacturers of semiconductors  and
products  incorporating  semiconductors,  pharmaceutical and chemical companies,
laboratories,  universities,  healthcare  providers,  government  agencies,  and
public and private research institutions.  Many factors, including public policy
spending  priorities,   available   resources,   and  economic  cycles,  have  a
significant  effect on the capital  spending  policies of these entities.  These
policies in turn can have a  significant  effect on the demand for our products.
For example,  sales of weighing and  inspection  equipment  have  decreased as a
result  of lower  demand  from  the  global  packaged  food  industry,  which is
undergoing a period of consolidation.



                                       4




                           FORWARD-LOOKING STATEMENTS

     This prospectus and the documents  incorporated by reference herein contain
forward-looking  statements.  These  statements  relate to future  events or our
future financial  performance.  In some cases, you can identify  forward-looking
statements  by  terminology   such  as  "may,"  "will,"   "should,"   "expects,"
"anticipates," "believes," "estimates," "predicts," "potential" or "continue" or
the negative of such terms or other comparable terminology. These statements are
only  predictions and involve known and unknown risks,  uncertainties  and other
factors, including the risks outlined under "Risk Factors" that may cause our or
our industry's actual results,  levels of activity,  performance or achievements
expressed  or implied by such  forward-looking  statements.  Before  deciding to
purchase our common stock you should  carefully  consider the risks described in
the "Risk Factors" section,  in additional to the other information set forth in
this prospectus and the documents incorporated by reference herein.

     Although we believe that the expectations  reflected in the forward-looking
statements  are  reasonable,  we  cannot  guarantee  future  results,  levels of
activity, performance or achievements. Moreover, neither we nor any other person
assumes responsibility for the accuracy and completeness of such statements.  We
are under no duty to update any of the forward-looking statements after the date
of this prospectus to conform such statement to actual results.

                                 USE OF PROCEEDS

     We will use the  proceeds  from the exercise of the  warrants,  if any, for
general corporate purposes.

                DESCRIPTION OF THE COMMON STOCK PURCHASE WARRANTS

     The warrants were  originally  issued to the Selling  Stockholders or their
affiliates by Thermo  TerraTech in private  placement  transactions  pursuant to
purchase  agreements  dated as of December  20, 1991,  March 20, 1992,  June 15,
1992,  September 1, 1992,  December 16, 1992, and March 18, 1993. On October 19,
1999, Thermo TerraTech and Thermo Electron entered into an Agreement and Plan of
Merger,  pursuant  to  which  Thermo  TerraTech  was  merged  with  and  into  a
wholly-owned subsidiary of Thermo Electron on September 22, 2000. In the merger,
each share of Thermo TerraTech common stock outstanding immediately prior to the
effective time of the merger,  other than shares held by Thermo TerraTech in its
treasury and shares held by Thermo  Electron,  was  converted  into the right to
receive 0.3945 share of Thermo Electron common stock.

     Under the terms of the merger  agreement,  Thermo Electron agreed to assume
the  warrants  issued  by  Thermo  TerraTech  and  convert  them  into  warrants
exercisable for Thermo  Electron common stock.  Under the terms of the warrants,
this action  resulted in an adjustment  to both the number of shares  underlying
the  warrants and the exercise  price of the  warrants.  The number of shares of
Thermo  TerraTech  common stock  underlying  the  warrants has been  adjusted by
multiplying  that  number by 0.3945.  In  addition,  the  exercise  price of the
warrants to purchase Thermo TerraTech common stock has been adjusted by dividing
that  number by 0.3945.  Accordingly,  a warrant to  purchase  12,000  shares of
Thermo TerraTech common stock for $11.34 per share has been adjusted as follows:

     12,000 shares of Thermo  TerraTech  common stock x 0.3945 = 4,734 shares of
Thermo Electron common stock

     Exercisable at $11.34 per share / 0.3945 = Exercisable at $28.75 per share

     All other terms and  conditions  of the warrants have remained the same, as
described below.

     Exercise  Period and  Procedure.  The  registered  holder of a warrant  may
exercise the warrant,  in whole or in part, but not as to fractional  shares, at
any time and from time to time  before  April 24,  2002.  Thermo  Electron  will
deliver  certificates  for shares  purchased  upon  exercise of a warrant to the
purchaser  within ten days after it receives a completed  and executed  exercise
agreement,  in the form attached to the warrant,  and a check  representing  the
exercise price of the shares for which the warrant is exercised. Thermo Electron
will deem shares  issuable upon the exercise of a warrant to have been issued to
the purchaser on the exercise  date of the warrant,  and will deem the purchaser
for all  purposes to have been the record  holder of such shares on the exercise
date.  Unless an  exercised  warrant has expired or all of the  purchase  rights
represented by the warrant have been  exercised,  Thermo Electron will prepare a
new warrant,  substantially identical thereto,  representing the rights formerly
represented  by the  warrant  which  have not  expired  or been  exercised.  The


                                       5


warrants may not be exercised as to  fractional  shares.  If a fractional  share
would  otherwise be issuable upon exercise of a warrant,  Thermo  Electron will,
within ten days  after the  exercise  date,  deliver  to the  purchaser  a check
payable to the purchaser in lieu of the fractional  share, in an amount equal to
the market  price of the  fractional  share as of the close of  business  on the
exercise date.

     The issuance of certificates  for shares upon exercise of a warrant will be
made without charge to the  registered  holder for any issuance tax or any other
cost incurred by Thermo Electron in connection with the exercise and the related
issuance of shares.  Thermo Electron will not,  however,  be required to pay any
tax which may be payable in respect of any transfer, in whole or in part, of any
warrant,  or the delivery of stock certificates in a name other than that of the
registered  holder of a warrant  presented for  exercise,  and any necessary tax
must be paid by the registered holder at the time of presentation.

     Thermo  Electron  will not close its books for the transfer of the warrants
or of any shares  issued or issuable  upon the  exercise on the  warrants in any
manner which interferes with the timely exercise of the warrants.

     Exercise Price.  The warrants  issued  pursuant to the purchase  agreements
dated as of December 20, 1991,  March 20, 1992,  June 15, 1992 and  September 1,
1992 may be exercised at an adjusted exercise price of $25.35 per share, and the
warrants  issued  pursuant to the purchase  agreements  dated as of December 16,
1992 and March 18, 1993 may be exercised at an adjusted exercise price of $28.75
per share.  The exercise  price of each  warrant was  originally  determined  by
Thermo TerraTech after taking into account several factors, including

     o the fair market  values of the common  stock  underlying  the warrants on
their respective dates of issuance,

     o the  appropriate  premiums  over  such fair  market  values  compared  to
premiums applicable to listed or quoted options on similar securities,

     o the degree of volatility in the fair market values prior to such issuance
and

     o the length of the exercise period of the warrants.

     Adjustments.  In order to prevent  dilution of the rights granted under the
warrants,  both the  exercise  price and the number of shares that may be issued
upon exercise of the warrants  will be subject to  adjustment  from time to time
if, during the exercise period, Thermo Electron

     o issues any shares of common stock as a dividend upon its common stock,
     o issues any shares of common stock by reclassification or otherwise,
     o combines its outstanding shares of common stock, by  reclassification  or
otherwise or
     o declares a dividend upon the common stock payable  otherwise  than out of
earnings or retained earnings and otherwise than in common stock.

     No  adjustment  of the  exercise  price  will be made if the  amount of the
adjustment  would  be less  than  one  cent  per  share,  but in that  case  any
adjustment  that would  otherwise  be  required  then to be made will be carried
forward  and  will be made at the  time and  together  with the next  adjustment
which,  together with any adjustment or adjustments  so carried  forward,  would
amount  to not  less  than  one  cent per  share.  Upon  any  reorganization  or
reclassification  of the capital stock of Thermo Electron,  or any consolidation
or  merger  of  Thermo   Electron  with  another   corporation,   other  than  a
consolidation  or merger in which Thermo  Electron is the  surviving  entity and
which does not result in any  change in the common  stock,  or any sale or other
disposition by Thermo Electron of all or substantially  all of its assets to any
other  corporation,  the terms of the warrants will be adjusted as follows.  The
warrants will,  after those events,  be exercisable  for the number of shares of
stock or other  securities or property of Thermo  Electron,  or of the successor
corporation that results from the  consolidation or merger,  as the case may be,
to which the shares, and any other securities and property,  of Thermo Electron,
deliverable  upon the exercise of the  warrants,  would have been  entitled upon
such reorganization,  reclassification of capital stock, consolidation,  merger,
sale or other disposition if the warrants had been exercised  immediately before
the reorganization,  reclassification of capital stock,  consolidation,  merger,
sale or other disposition.

     No Voting Rights. The warrants will not entitle their holders to any voting
rights or other rights as stockholders of Thermo Electron.

     Miscellaneous.  The warrants and all rights thereunder are transferable, in
whole or in part, without charge to the registered holder, upon surrender of the
warrants  with a  properly  executed  assignment,  in the form  attached  to the
warrants,  at the  principal  office of Thermo  Electron.  The  warrants  may be
amended,  and  Thermo  Electron  may take  actions  that are  prohibited  by the
warrants, or omit to take actions that it is required to perform, only if Thermo
Electron  has   obtained  the  written   consent  of  the  holders  of  warrants
representing  at least 50% of the shares  obtainable  upon the  exercise  of the
warrants outstanding at the time of that consent.


                                       6





                              SELLING STOCKHOLDERS

     The following table lists the Selling  Stockholders  and other  information
regarding the beneficial  ownership of the common stock  underlying the warrants
by each of the  Selling  Stockholders  as of April  30,  2001.  The  information
provided in the table below has been obtained from the Selling Stockholders. The
Selling  Stockholders  may  sell  all,  some  or none of  their  shares  in this
offering. See "Plan of Distribution."


                                                                  


                             Number of Shares          Maximum Number      Shares
Names of Selling             Underlying Warrants       Of Shares           Beneficially
                             Owned Prior to            Being               Owned After
                             Offering                                      Offering(1)
Stockholders                                           Offered
--------------------------   ------------------------  ------------------  -----------------


Irving B. Harris                  81,070                    81,070                 0
Revocable
Trust dated 7/31/87 (2)
Roxanne H. Frank Trust            25,544                    25,544                 0
    dated 3/16/84(3)
Couderay Partners(3)              23,374                    23,374                 0
Virginia H. Polsky                21,796                    21,796                 0
Trust
   dated 8/5/84(3)
Jerome Kahn, Jr.                   8,383                     8,383                 0
Revocable     Trust,
dated 10/16/87,
Jerome   Kahn, Jr.,
Trustee (3)
Fred Holubow(4)                    6,509                     6,509                 0
Marc A. Neuerman                   2,762                     2,762                 0
Yves Micheli                       2,466                     2,466                 0
Bear East Partners                11,070                    11,070                 0
Terence M. Hogan                     864                       864                 0
William W. Harris                  2,367                     2,367                 0
Children Charity Trust
dated 11/29/83(3)
William W. Harris                 13,413                    13,413                 0
Trust
     dated 6/22/84(3)
Harris Foundation(2)              18,936                    18,936                 0
Irving B. Harris                   1,578                     1,578                 0
Foundation(2)
John N. Hatsopoulos(5)             4,931                     4,931                 0
Darier, Hentsch & Cie.             4,931                     4,931                 0
Joseph Giamanco                    4,931                     4,931                 0
Peter G. Pantazelos                5,918                     5,918                 0
The George and Dora                3,945                     3,945                 0
Razis    1981 Trust(6)
IBH Grandchildren                  4,734                     4,734                 0
Charity    Trust dated
11/29/83(3)
Donna E. Barrows                   5,523                     5,523                 0
June H. Barrows                    7,890                     7,890                 0
William Harris Settlor             1,578                     1,578                 0
Trust, F/B/O Patricia
J. Rosbrow(2)
Robert L. Barrows                  4,734                     4,734                 0
James J. Pelts                     1,578                     1,578                 0
Mary Ann Wark                      3,945                     3,945                 0
Joan W. Harris(2)                  1,578                     1,578                 0




(1) Assumes that all of the shares  underlying  the warrants held by the Selling
Stockholders  and being  offered  under this  prospectus  are sold.  None of the
Selling Stockholders owns more than one percent of common stock of the company.

                                       7


(2) Mr. Irving B. Harris,  trustee of the Irving B. Harris  Revocable  Trust, is
also  Chairman  of the  Harris  Foundation;  Chairman  of the  Irving B.  Harris
Foundation;  a trustee of the William Harris  Settlor  Trust,  F/B/O Patricia J.
Rosbrow;  and the  husband of Joan W.  Harris.  Accordingly,  Mr.  Harris may be
deemed to own the 18.936, 1,578, 1,578 and 1,578 shares underlying the warrants,
respectively, owned by those warrantholders.

(3) Mr. Jerome Kahn, Jr.,  trustee of the Jerome Kahn, Jr.  Revocable Trust, and
Mr.  Marc A.  Neuerman  are also  trustees  of the  Roxanne H. Frank Trust dated
3/16/84;  managing  agents of Couderay  Partners;  trustees  of the  Virginia H.
Polsky Trust dated 8/5/84;  trustees of the William W. Harris  Children  Charity
Trust dated 11/29/83; trustees of the William W. Harris Trust dated 6/22/84; and
trustees of the IBH Grandchildren Charity Trust dated 11/29/83. Accordingly, Mr.
Kahn and Mr.  Neuerman  may each be deemed to own the  25,544,  23,374,  21,796,
2,367, 13,413 and 4,734 shares underlying the warrants,  respectively,  owned by
those warrantholders.

(4) Mr. Holubow was a director of  ThermoRetec  Corporation  (`ThermoRetec"),  a
former  publicly-held  subsidiary  of the  company,  from 1992  until  2000 when
ThermoRetec  ceased  to be  publicly-held  and he is also a  director  of Thermo
Trilogy Corporation, a majority-owned subsidiary of the company.

(5) Mr.  Hatsopoulos  was Vice  Chairman of the company from  September  1998 to
February  2000, a director of the company from  September  1997 to February 2000
and served as a director of the following formerly publicly-held subsidiaries of
Thermo  Electron at various  times in the period  1998  through  February  2000:
Thermedics Inc.,  Thermo Fibertek Inc.,  Thermo  Instrument  Systems Inc. Thermo
Ecotek  Corporation,  Thermo  Power  Corporation  , Onix Systems Inc. and Thermo
TerraTech  Inc. He was the president of the company from 1997 to 1998, its chief
financial  officer from 1988 to 1998 and its executive  vice president from 1986
to 1998. He also served as senior vice president and chief financial  officer of
several of the company's subsidiaries from 1988 until 1998.

(6) Mr.  Paris  Nicolaides  is trustee  of The  George & Dora Razis 1981  Trust.
Accordingly, Mr. Nicolaides may be deemed to own the 3,945 shares underlying the
warrants owned by that trust.

     The shares  underlying  the warrants are being  registered to permit public
secondary  trading of the shares from time to time by the Selling  Stockholders.
All of  the  warrants  were  acquired  by  the  Selling  Stockholders  or  their
affiliates from Thermo TerraTech Inc. in private placement transactions pursuant
to Securities Purchase Agreements with Thermo TerraTech dated as of December 20,
1991, March 20, 1992, June 15, 1992,  September 1, 1992,  December 16, 1992, and
March 18, 1993.  202,181 of the warrants are exercisable at an exercise price of
$25.35 per share and 74,166 of the warrants are exercisable at an exercise price
of $28.75  per  Share.  Thermo  Electron  has  agreed to  prepare  and file such
amendments  and  supplements  to  the  Registration   Statement  of  which  this
Prospectus forms a part as may be necessary to keep the  Registration  Statement
effective until all the shares  underlying the warrants offered hereby have been
sold pursuant thereto, until such shares are no longer, by reason of Rule 144(k)
under the  Securities  Act or any other rule of similar  effect,  required to be
registered for the public sale thereof by the Selling Stockholders, or until the
warrants have expired by their terms.


                              PLAN OF DISTRIBUTION

     The Selling  Stockholders  may sell shares from time to time in  negotiated
transactions,  at fixed prices which may be changed, at market prices prevailing
at the time of sale,  at prices  related to such  prevailing  market price or at
negotiated  prices.  The Selling  Stockholders may effect these  transactions by
selling the shares to or through  broker-dealers,  and such  broker-dealers  may
receive  compensation in the form of discounts,  concessions or commissions from
the  Selling  Stockholders  and/or  the  purchasers  of the shares for whom such
broker-dealers  may act as agent or to whom  they  sell as  principal,  or both,
which compensation to a particular broker-dealer might be in excess of customary
commissions.

     The Selling  Stockholders and any broker-dealers who act in connection with
the sale of securities hereunder may be deemed to be "underwriters" as that term
is  defined in the  Securities  Act of 1933,  as  amended,  and any  commissions
received by them and profit on any resale of the  securities as principal  might
be deemed to be underwriting discounts and commissions under the Securities Act.
Thermo Electron will indemnify the Selling Stockholders against some liabilities
in connection with their sales,  including  liabilities under the Securities Act
as underwriter or otherwise.


                                       8


                                  LEGAL MATTERS

     The  validity of the common  stock  offered  hereby has been passed upon by
John A. Piccione,  Esq., Deputy General Counsel of Thermo Electron. Mr. Piccione
is a full-time employee of Thermo Electron, and owns or has the right to acquire
57,933 shares of common stock.

                                     EXPERTS

     Our financial statements  incorporated in this Prospectus by reference from
our Annual  Report on Form 10-K for the year ended  December  30, 2000 have been
audited by Arthur Andersen LLP, independent auditors, as stated in their report,
which is  incorporated  herein by reference,  and have been so  incorporated  in
reliance upon the authority of such firm as experts in giving such report.


                       WHERE YOU CAN FIND MORE INFORMATION

     We are a public  company and file annual,  quarterly  and special  reports,
proxy  statements  and  other  information  with  the  Securities  and  Exchange
Commission.  You may  read and copy any  document  we file at the  SEC's  public
reference  room at 450 Fifth  Street,  N.W.,  Washington,  D.C.  20549.  You can
request copies of these documents by writing to the SEC and paying a fee for the
copying cost. Please call the SEC at  1-800-SEC-0330  for more information about
the operation of the public  reference  room. Our SEC filings are also available
to the public at the SEC's web site at http://www.sec.gov.  In addition, you can
read and copy our SEC filings at the offices of the New York Stock Exchange,  20
Broad Street, New York, New York 10005.

      This prospectus is only part of a Registration Statement on Form S-3 that
we have filed with the SEC under the Securities Act and therefore omits certain
information contained in the Registration Statement. We have also filed exhibits
and schedules with the Registration Statement that are excluded from this
prospectus, and you should refer to the applicable exhibit or schedule for a
complete description of any statement referring to any contract or other
document. You may inspect a copy of the Registration Statement, including the
exhibits and schedules, without charge at the public reference room, or obtain a
copy from the SEC upon payment of the fees prescribed by the SEC.

                     INCORPORATION OF DOCUMENTS BY REFERENCE

     The SEC allows us to  "incorporate  by reference"  the  information we file
with it,  which  means  that we can  disclose  important  information  to you by
referring you to those documents.  The information  incorporated by reference is
considered to be part of this  prospectus and information we file later with the
SEC will automatically update and supersede this information.  We incorporate by
reference  the documents  listed below and any future  filings made with the SEC
under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934.
The documents we are incorporating by reference are:

          (1)  Annual Report on Form 10-K for the fiscal year ended December 30,
               2000;

          (2)  Current Report on Form 8-K, filed with the SEC on April 30, 2001;

          (3)  The  description  of our common  stock which is  contained in our
               Registration  Statement on Form 8-A filed under the Exchange Act,
               as that description may be amended from time to time; and

          (4)  The  description of our Preferred  Stock Purchase Rights which is
               contained in our  Registration  Statement on Form 8-A filed under
               the Exchange Act, as that description may be amended from time to
               time.

     All reports or proxy  statements  that we file pursuant to Sections  13(a),
13(c),  14 and 15(d) of the  Exchange  Act  after the date of this  Registration
Statement and before the filing of a  post-effective  amendment  that  indicates
that all  securities  offered  herein have been sold,  or that  deregisters  all
securities  then remaining  unsold,  will be  incorporated  by reference in this
Registration  Statement and to be a part of this document from the dates we file
those documents.


                                       9






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You should rely only on the information
                                                     THERMO ELECTRON CORPORATION
You  should  rely  only on the  information
contained in this  prospectus.  We have not               276,348 shares of
authorized   anyone  to  provide  you  with                 Common Stock
information  different  from that contained          ($1.00 par value per share)
in    this    prospectus.    The    Selling
Stockholders   are  offering  to  sell  and
seeking  offers to buy shares of our common               ________________
stock only in  jurisdictions  where  offers
and sales are  permitted.  The  information                  PROSPECTUS
contained  in this  prospectus  is accurate               ________________
only as of May 10,  2001.  You  should  not
assume that this  prospectus is accurate as
of any other date.


         TABLE OF CONTENTS
                                        Page

Thermo Electron's Business.........      1
Risk Factors.......................      2
Forward-Looking Statements.........      5
Use of Proceeds....................      5
Description of the Common Stock
Purchase Warrants..................      5
Selling Stockholders...............      8
Plan of Distribution...............      9
Legal Matters......................     10
Experts............................     10
Where You Can Find More Information     10
Incorporation of Documents by           10
Reference..........................

                                                            May 10, 2001


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