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                                                                     EXHIBIT 5.1





                                 June 30, 1995



UniFirst Corporation
68 Jonspin Road
Wilmington, Massachusetts 01887

         Re:     UniFirst Corporation Profit Sharing Plan

Ladies and Gentlemen:

         This opinion is furnished in connection with the registration pursuant
to the Securities Act of 1933, as amended (the "Act"), of 500,000 shares (the
"Shares") of Common Stock, par value $.10 per share (the "Common Stock"), of
UniFirst Corporation (the "Company") which may be acquired by eligible
employees of the Company and certain of its affiliates under the provisions of
the UniFirst Corporation Profit Sharing Plan (the "Plan") and of interests in
the Plan.

         We have acted as counsel to the Company in connection with the
registration of the Shares and interests in the Plan under the Act.  We have
examined the Restated Articles of Organization, as amended, and the By-laws, as
amended, of the Company; such records of the corporate proceedings of the
Company as we deemed necessary; a Registration Statement on Form S-8 under the
Act relating to the Shares (the "Registration Statement"); the Plan; and such
other certificates, receipts, records and documents as we considered necessary
for the purposes of this opinion.

         We are attorneys admitted to practice in the Commonwealth of
Massachusetts.  We express no opinion concerning the laws of any jurisdictions
other than the laws of the United States of America and the Commonwealth of
Massachusetts.

         Based upon the foregoing, we are of the opinion that when the Shares
have been issued and paid for in accordance with the terms of the Plan, the
Shares will be validly issued, fully paid and non-assessable shares of the
Company's Common Stock.

         The foregoing assumes that all requisite steps will be taken to comply
with the requirements of the Act and applicable requirements of state laws
regulating the offer and sale of securities.
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                 We hereby consent to the filing of this opinion as an exhibit
to the above-referenced Registration Statement.

                                                    Very truly yours,


                                                    /s/ Goodwin, Procter & Hoar
                                                    ---------------------------
                                                    GOODWIN, PROCTER & HOAR