As filed with the Securities and Exchange Commission on June 20, 2001
                                                     Registration No. 333-38782
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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


                         POST-EFFECTIVE AMENDMENT NO. 1
                                       TO
                                    FORM S-3
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933


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

                       VITESSE SEMICONDUCTOR CORPORATION
             (Exact Name of Registrant as Specified in Its Charter)


                  Delaware                            77-0138960
      (State or other jurisdiction of              (I.R.S. Employer
       incorporation or organization)           Identification Number)


                                741 Calle Plano
                              Camarillo, CA 93012
                                 (805) 388-3700
    (Address, including zip code, and telephone number, including area code,
                 of Registrant's principal executive offices)

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


                               Eugene F. Hovanec
                            Chief Financial Officer
                       Vitesse Semiconductor Corporation
                                741 Calle Plano
                              Camarillo, CA 93012
                                 (805) 388-3700


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

 (Name, address, including zip code, and telephone number, including area code,
                             of agent for service)

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

                                   Copies to:
                               Francis S. Currie
                             Davis Polk & Wardwell
                              1600 El Camino Real
                              Menlo Park, CA 94025
                                 (650) 752-2000


     Approximate date of commencement of proposed sale to the public: From time
to time after the original effective date of this Registration Statement.

     If the only securities being registered on this Form are to be offered
pursuant to dividend or reinvestment plans, check the following box. [ ]

     If the only securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, please check the following box. [X]


     If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following
box and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. [ ]

     If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [ ]

     If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box. [ ]






     Vitesse Semiconductor Corporation hereby withdraws from registration
3,245,410 shares of our common stock registered for resale hereon which have
not been sold during the time we have agreed to keep this Registration
Statement Effective.


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


     Pursuant to the requirements of the Securities Act of 1933, the Registrant
has duly caused this Post-Effective Amendment No. 1 to the Registration
Statement to be signed on its behalf by the undersigned, thereto duly
authorized, in the city of Camarillo, State of California on June 19, 2001.



                                   SIGNATURES


                                           VITESSE SEMICONDUCTOR CORPORATION



                                           By: /s/ Eugene F. Hovenec
                                               ---------------------------------
                                               Name:  Eugene F. Hovanec
                                               Title: Chief Financial Officer


     Pursuant to the requirements of the Securities Act of 1933, this Amendment
has been signed by the following persons in the capacities and on the dates
indicated.


      Signature                          Title                        Date
      ---------                          -----                        ----
/s/ Louis R. Tomasetta*
- -----------------------------      Chief Executive Officer        June 19, 2001
Louis R. Tamasetta

/s/ Eugene F. Hovanec
- -----------------------------      Chief Financial Officer        June 19, 2001
Eugene F. Hovanec

/s/ James A. Cole*
- -----------------------------      Director                       June 19, 2001
James A. Cole

/s/ Pierre R. Lamond*
- -----------------------------      Chairman of The Board          June 19, 2001
Pierre R. Lamond

/s/ John C. Lewis*
- -----------------------------      Director                       June 19, 2001
John C. Lewis

/s/ Alex Daly*
- -----------------------------      Director                       June 19, 2001
Alex Daly

/s/ Vincent Chan*
- -----------------------------      Director                       June 19, 2001
Vincent Chan


*By: /s/ Eugene F. Hovanec
- -----------------------------
Eugene F. Hovanec
Attorney in Fact


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