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

I, Ralph Rubio, Chief Executive Officer of Rubio's Restaurants, Inc. (the
"Company"), do hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

            (a)   the Quarterly Report on Form 10-Q of the Company for the
                  quarter ended June 27, 2004, as filed with the Securities and
                  Exchange Commission (the "Report"), fully complies with the
                  requirements of Section 13(a) or 15(d) of the Securities
                  Exchange Act of 1934; and

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

Dated: August 9, 2004                              /s/ Ralph Rubio
                                                   -----------------------------
                                                   Ralph Rubio
                                                   Chief Executive Officer

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.

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