



                            TELECOPIER (513) 579-6457


                                February 18, 1999




Direct Dial:  (513) 579-6560





Cintas Corporation
6800 Cintas Boulevard
Cincinnati, Ohio  45262

Gentlemen:

     We serve as your  General  Counsel and are familiar  with your  Articles of
Incorporation, By-laws and corporate proceedings. On this basis, we have made an
examination as to:

        1.     The organization of Cintas Corporation;

        2.  The  legal  sufficiency  of  all  corporate  proceedings  of  Cintas
Corporation in connection with the  authorization  and issuance of all presently
outstanding and issued Common Stock of Cintas Corporation; and

        3.  The  legal  sufficiency  of  all  corporate   proceedings  taken  in
connection  with the  authorization  of the issuance of 16,343  shares of Common
Stock to be included in a  Registration  Statement  on Form S-3 to be filed with
the Securities and Exchange Commission.

        Based upon such examination, we are of the opinion that:

     1. Cintas Corporation is a duly organized and validly existing  corporation
under the laws of the State of Washington;





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Cintas Corporation
Page 2
February 18, 1999


        2. Cintas  Corporation  has taken all necessary  and required  corporate
actions in connection  with the issuance of 16,343 shares of newly issued Common
Stock and the aforesaid  16,343  shares of Common Stock are validly  authorized,
legally  issued,  fully  paid and  nonassessable  shares of Common  Stock of the
Corporation free of any preemptive rights.

        We hereby  consent to be named in the aforesaid  Registration  Statement
and the  Prospectus  part  thereof  as the  attorneys  who will pass upon  legal
matters in connection with the issuance of the aforesaid Common Stock and to the
filing  of  this  opinion  as an  exhibit  to  the  Registration  Statement  and
furthermore  consent  to  references  made  to  this  firm  in the  Registration
Statement.


                                         Very truly yours,

                                         KEATING, MUETHING & KLEKAMP, P.L.L.


                                         BY:/s/ Robert E. Coletti
                                            -------------------------
                                               Robert E. Coletti



