Exhibit 99.1


                CHIEF EXECUTIVE OFFICER 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 Monterey Bay Bancorp,  Inc.  (the
"Company")  on Form 10-Q for the period  ending March 31, 2003 as filed with the
Securities  and Exchange  Commission  on the date hereof (the  "Report"),  I, C.
Edward Holden, 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.


                                        Monterey Bay Bancorp, Inc.




Date:    May 12, 2003                   By:      /s/ C. Edward Holden
                                                 --------------------
                                                 C. Edward Holden
                                                 Chief Executive Officer



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