Exhibit 32.1

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

      The undersigned officer of UniFirst Corporation (the "Company") hereby
certifies that the Company's quarterly report on Form 10-Q for the period ended
November 29, 2003 (the "Report"), as filed with the Securities and Exchange
Commission on the date hereof, fully complies with the requirements of Section
13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934, as
amended, and that the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company. This certification is provided solely pursuant to 18 U.S.C. Section
1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, and
shall not be deemed to be part of the Report or "filed" for any purpose
whatsoever.

Date: January 13, 2004

                                 By: /s/ Ronald D. Croatti
                                     ------------------------------------------
                                     Ronald D. Croatti, Chief Executive Officer
                                     (Principal Executive Officer)


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