SECURITIES AND EXCHANGE COMMISSION

                              WASHINGTON, DC 20549
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                    AMENDMENT NO. 1 ON FORM 10-K/A TO FORM 10-K

(mark one)

[X] Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act
of 1934 for the fiscal year ended January 1, 2000

[ ] Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange
Act of 1934

                           Commission file number 1-8002

                            THERMO ELECTRON CORPORATION
               (Exact name of Registrant as specified in its charter)

Delaware                                                             04-2209186
State or other jurisdiction of                                 (I.R.S. Employer
(incorporation or organization)                             Identification No.)

81 Wyman Street,
P.O. Box 9046
Waltham, Massachusetts                                               02454-9046
(Address of principal executive offices)                             (Zip Code)

       Registrant's telephone number, including area code: (781) 622-1000

           Securities registered pursuant to Section 12(b) of the Act:

Title of each class                Name of each  exchange  on which  registered
Common  Stock, $1.00 par value                    New York Stock Exchange
Preferred Stock Purchase Rights

           Securities registered pursuant to Section 12(g) of the Act:
                                      None

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months, and (2) has been subject to the filing requirements for
at least the past 90 days. Yes [ X ] No [ ]

Indicate by check mark if disclosure of delinquent  filers  pursuant to Item 405
of Regulation  S-K is not contained  herein,  and will not be contained,  to the
best  of  the  Registrant's   knowledge,  in  definitive  proxy  or  information
statements  incorporated  by  reference  into  Part III of this Form 10-K or any
amendment to this Form 10-K. [ ]


The  aggregate  market  value of the voting stock held by  nonaffiliates  of the
Registrant as of January 28, 2000, was approximately $2,493,791,000.

As of January 28, 2000, the Registrant  had  156,800,687  shares of Common Stock
outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

Portions of the  Registrant's  Annual Report to Shareholders  for the year ended
January 1, 2000, are incorporated by reference into Parts I and II.

Portions of the  Registrant's  definitive Proxy Statement for the Annual Meeting
of Shareholders  to be held on May 18, 2000, are  incorporated by reference into
Part III.





Item 5 of the  Registrant's  Form 10-K for the fiscal year ended January 1, 2000
is hereby amended and restated to read as follows:

Item 5. Market for Registrant's Common Equity and Related Stockholder Matters

Information  concerning the market and market price for the Registrant's  common
stock,  $1.00 par value,  and dividend  policy,  is included  under the sections
labeled  "Common  Stock  Market   Information"  and  "Dividend  Policy"  in  the
Registrant's  1999 Annual Report to Shareholders  and is incorporated  herein by
reference.

During  1998  and  1999,  in a  series  of  transactions  with an  institutional
counterparty,  the  Registrant  sold put options on an  aggregate  of  5,701,000
shares of its  common  stock and  purchased  call  options  on an  aggregate  of
2,850,500 shares of its common stock. These transactions were entered into as an
alternative to the Registrant's  repurchases of its shares under its traditional
stock repurchase  program.  No cash was exchanged as a result of these so-called
"costless  collar"  transactions.  Following  is  a  chart  showing  information
relating to the put and call options:

Put Options:

 Trade Date        Expiration Date           Number of Options    Exercise Price
                                                                    per Share
November 27, 1998  November 29, 1999              900,000              $16.35
December 10, 1998  December 10, 1999              767,000              $15.56
October 9, 1998    April 7, 2000                1,667,000              $14.43
October 22, 1998   January 21, 2000             1,667,000              $13.85
March 25, 1999     May 25, 2000                   700,000              $13.17

Call Options:

 Trade Date        Expiration Date           Number of Options    Exercise Price
                                                                     per Share
November 27, 1998  November 29, 1999              450,000              $17.44
December 10, 1998  December 10, 1999              383,500              $16.60
October 9, 1998    April 7, 2000                  833,500              $15.15
October 22, 1998   January 21, 2000               833,500              $14.65
March 25, 1999     May 25, 2000                   350,000              $13.84

     As of March 22,  2000,  the date on which  this  Form  10-K was  originally
filed, the Registrant had a remaining maximum potential obligation under the put
options to buy back  2,367,000  shares at a weighted  average  exercise price of
$14.06  for an  aggregate  of $33.3  million.  These  put and call  options  are
exercisable  only at  maturity  and  expire  between  April  and May  2000.  The
Registrant has the right to settle the put options by physical settlement of the
options  or by net share  settlement  using  shares of the  Registrant's  common
stock. Under the call options remaining as of March 22, 2000, the Registrant has
the right, but not the obligation,  to purchase from the counterparty  1,183,500
shares of its common stock at an average price per share of $14.76 in 2000.  The
Registrant  may, from time to time,  enter into  additional  put and call option
arrangements.  During 1999, the  Registrant  purchased  1,536,000  shares of its
common  stock under the put options for $24.6  million.  During 1999 and January
2000, put options for 1,798,000 shares expired.  Each of these  transactions was
exempt from  registration  under Section 4(2) of the  Securities Act of 1933, as
amended.






FORM 10-K/A

                            THERMO ELECTRON CORPORATION

                                   SIGNATURES

      Pursuant  to the  requirements  of Section  13 or 15(d) of the  Securities
Exchange Act of 1934,  the  Registrant  has duly caused this  Amendment No. 1 on
Form  10-K/A to be  signed on its  behalf  by the  undersigned,  thereunto  duly
authorized.


                           THERMO ELECTRON CORPORATION



                               By: /s/ Theo Melas-Kyriazi
                                   ------------------------------------------
                                   Theo Melas-Kyriazi
                                   Vice President and Chief Financial Officer
                                   (Principal Financial and Accounting Officer)








Date: June 27, 2000