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                                                                     EXHIBIT 5.1

                         [PALMER & DODGE LLP LETTERHEAD]


                                September 7, 2000

Lamar Advertising Company
5551 Corporate Boulevard
Baton Rouge, Louisiana 70808


         We are rendering this opinion in connection with the Registration
Statement on Form S-3 (the "Registration Statement") filed by Lamar Advertising
Company (the "Company") with the Securities and Exchange Commission under the
Securities Act of 1933, as amended, on or about the date hereof. The
Registration Statement relates to the registration of up to 26,227,273 shares
(the "Class A Shares") of the Company's Class A Common Stock, $0.001 par value.

         We have acted as your counsel in connection with the preparation of the
Registration Statement. We are familiar with the proceedings of the Board of
Directors in connection with the authorization and issuance of the Class A
Shares. We have examined all such documents as we consider necessary to enable
us to render this opinion.

         Based upon the foregoing, we are of the opinion that the Class A Shares
have been duly authorized and are validly issued, fully paid and non-assessable.

         The foregoing opinion is limited to Delaware General Corporation Law,
including the applicable provisions of the Delaware Constitution and reported
judicial decisions interpreting these laws, and the federal laws of the United
States.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under "Legal Matters."

                                             Very truly yours,

                                             /s/ Palmer & Dodge LLP


