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                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549
 
                                  FORM 10-K/A
 
(MARK ONE)
[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES
    EXCHANGE ACT OF 1934

    For the fiscal year ended September 30, 1996
                                      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: 0-19654
 
                       VITESSE SEMICONDUCTOR CORPORATION
            (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
 
               DELAWARE                              77-0138960
    (State or other jurisdiction of        (I.R.S. Employer Identification
    incorporation or organization)                     Number)
 
 
      741 CALLE PLANO 
    CAMARILLO, CALIFORNIA                              93012
(Address of principal executive                     (Zip Code)
          offices)
 
      Registrant's telephone number, including area code: (805) 388-3700
 
       Securities registered pursuant to Section 12(b) of the Act: NONE
 
          Securities registered pursuant to Section 12(g) of the Act:
                         COMMON STOCK, $.01 PAR VALUE
                               (TITLE OF CLASS)
 
  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 [_]
 
  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 in Part III of this Form 10-K or any
amendment to this Form 10-K. [X]
 
  The aggregate market value of the voting stock held by non-affiliates of the
registrant, based upon the closing sale price of the Common Stock on September
30, 1996 as reported on the Nasdaq National Market, was approximately
$726,000,000. Shares of Common Stock held by each officer and director and by
each person who owns 5% or more of the outstanding Common Stock have been
excluded in that such persons may be deemed to be affiliates. This
determination of affiliate status is not necessarily a conclusive
determination for other purposes.
 
  As of September 30, 1996, the registrant had outstanding 19,406,527 shares
of Common Stock.
 
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                                  SIGNATURES

     Pursuant to the requirements of Section 13 or (15d) 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.

                                       VITESSE SEMICONDUCTOR CORPORATION

Date: December 20, 1996                By:      /s/ EUGENE F. HOVANEC
                                           ----------------------------------
                                           Eugene F. Hovanec
                                           Vice President, Finance and 
                                           Chief Financial Officer

     Pursuant to the requirements of the Securities Exchange Act of 1934, this 
report has been signed below by the followng persons on behalf of the registrant
and in the capacities and on the dates indicated.

<TABLE> 
<CAPTION> 
         SIGNATURE                           TITLE                    DATE
         ---------                           -----                    ----
<S>                            <C>                             <C> 
  /s/ LOUIS R. TOMASETTA*      President and Chief Executive   December 20, 1996
---------------------------      Officer (Principal Executive
      Louis R. Tomasetta         Officer)

   /s/ EUGENE F. HOVANEC       Vice President, Finance and     December 20, 1996
---------------------------      Chief Financial Officer
       Eugene F. Hovanec         (Principal Financial and
                                 Accounting Officer)

    /s/ JAMES A. COLE*         Director                        December 20, 1996
---------------------------      
        James A. Cole

   /s/ PIERRE R. LAMOND*       Chairman of the Board of        December 20, 1996
---------------------------      Directors
       Pierre R. Lamond

    /s/ JOHN C. LEWIS*         Director                        December 20, 1996
---------------------------      
        John C. Lewis

     /s/ T.J. RODGERS*         Director                        December 20, 1996
---------------------------      
         T.J. Rodgers

*By  /s/ EUGENE F. HOVANEC*
    -----------------------
         Eugene F. Hovanec
</TABLE> 

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