Exhibit 32.1

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

                  In connection with the Quarterly Report of Vicor Corporation
(the "Company") on Form 10-Q for the period ending September 30, 2003 as filed
with the Securities and Exchange Commission on the date hereof (the "Report"),
I, Patrizio Vinciarelli, Chief Executive Officer of the Company, certify,
pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, that:

         (1)   The Report fully complies with the requirements of Section 13(a)
               or 15(d) of the Securities Exchange Act of 1934; and

         (2)   The information contained in the Report fairly presents, in all
               material respects, the financial condition and results of
               operations of the Company.

/s/Patrizio Vinciarelli
- -----------------------------------
Patrizio Vinciarelli
President, Chairman of the Board and
Chief Executive Officer

November 5, 2003

                  A signed original of this written statement required by
Section 906 has been provided to the Company and will be retained by the Company
and furnished to the Securities and Exchange Commission or its staff upon
request.