Registration No. 333-72561 filed pursuant to Rule 424(b)(3) PROSPECTUS SUPPLEMENT Dated April 1, 1999 to the Prospectus dated March 15, 1999 CINTAS CORPORATION 16,343 shares of Common Stock Cintas Corporation, a Washington corporation, has prepared this Prospectus Supplement to update certain information included in its Prospectus dated March 15, 1999 relating to 16,343 shares of Common Stock, without par value. These shares are being offered for sale by certain shareholders of the Company. 15,526 of the 16,343 shares of Common Stock owned by David Feder and Mindy Feder, as joint tenants, included in the Prospectus are subject to a pledge and security agreement in favor of Merrill Lynch. Following a transfer of such shares to Merrill Lynch pursuant to such a pledge and security agreement, such shares may be sold by Merrill Lynch pursuant to the Prospectus.