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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                AMENDMENT NO. 1
                                       TO

                                  FORM 10-Q/A

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(Mark One)
[X]   QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934

              For the quarterly period ended December 26, 1999

                                       or

[ ]   TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934

               For the transition period from _______ to _______

                         Commission file number: 0-15086

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                             SUN MICROSYSTEMS, INC.
             (Exact Name of registrant as specified in its charter)

                DELAWARE                              94-2805249
  (State or other jurisdiction of        (I.R.S. Employer Identification No.)
   incorporation or organization)


                    901 SAN ANTONIO ROAD, PALO ALTO, CA 94303
             (Address of principal executive offices with zip code)

                                 (650) 960-1300
              (Registrant's telephone number, including area code)

                                       N/A
              (Former name, former address and former fiscal year,
                         if changed since last report)

                              --------------------

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 (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                          YES [X]           NO [ ]


                      APPLICABLE ONLY TO CORPORATE ISSUERS:

Indicate the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practical date.

                 CLASS                       OUTSTANDING AT DECEMBER 26, 1999
  Common Stock - $0.00067 par value                   1,578,501,057


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                                     INDEX

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COVER PAGE                                                                    1

INDEX                                                                         2

SIGNATURES                                                                    3
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SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                   SUN MICROSYSTEMS, INC.


                                   BY


                                        /s/ MICHAEL E. LEHMAN
                                        ---------------------------------------
                                        Michael E. Lehman
                                        Vice President, Corporate Resources
                                        and Chief Financial Officer

                                        /s/ MICHAEL L. POPOV
                                        ---------------------------------------
                                        Michael L. Popov
                                        Vice President and Corporate Controller,
                                        Chief Accounting Officer

Dated: February 16, 2000