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EXHIBIT 32.1
CERTIFICATION OF CHIEF EXECUTIVE OFFICER

Pursuant to 18 U.S.C. § 1350, as adopted pursuant to
§ 906 of the Sarbanes-Oxley Act of 2002

        In connection with the filing with the Securities and Exchange Commission of the Report of Cintas Corporation (the "Company") on Form 10-K for the period ending May 31, 2003 (the "Report"), I, Scott D. Farmer, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that to the best of my knowledge:

        (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/  SCOTT D. FARMER Scott D. Farmer
Principal Executive Officer

August 29, 2003

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EXHIBIT 32.1 CERTIFICATION OF CHIEF EXECUTIVE OFFICER Pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002