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                [Keating, Muething & Klekamp, P.L.L. Letterhead]






 GARY P. KREIDER
 DIRECT DIAL:  (513) 579-6411
 FACSIMILE: (513) 579-6956
 E-MAIL: GKREIDER@KMKLAW.COM




                                                                       EXHIBIT 5
                                February 16, 1999


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 shares of Common Stock pursuant to an
Agreement and Plan of Merger dated January 9, 1999 among Unitog Company, Cintas
Corporation and Cintas Image Acquisition Company that are included in a 
Registration Statement on Form S-4 filed with the Securities and Exchange 
Commission in connection with that Agreement.

      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;

      2. Cintas Corporation has taken all necessary and required corporate
actions in connection with the issuance of Common Stock pursuant to an Agreement
and Plan of Merger dated January 9, 1999 among Unitog Company, Cintas
Corporation and Cintas Image Acquisition Company and when issued those shares of
Common Stock will be validly authorized, legally issued, fully paid and
nonassessable shares of Common Stock of Cintas Corporation free of any
preemptive rights.


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      We hereby consent to the reference to our firm in the Registration
Statement and the Prospectus part thereof as the attorneys who will pass upon
legal matters in connection with the issuance of such shares of Common Stock and
to the filing of this opinion as an exhibit to the Registration Statement. In
providing this consent, we do not admit that we are within the category of
persons whose consent is required under Section 7 of the Securities Act of 1933
or the rules and regulations of the Commission promulgated thereunder.

                                           Very truly yours,


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



                                           BY: /s/ Gary P. Kreider
                                              ---------------------------------
                                              Gary P. Kreider