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                                                                    EXHIBIT 23.1

               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

Regarding:

     1)   Registration Statement on Form S-8 relating to F.N.B. Corporation 1990
          Stock Option Plan (File #33-78114).

     2)   Registration Statement on Form S-8 relating to F.N.B. Corporation
          Restricted Stock Bonus Plan (File #33-78134).

     3)   Registration Statement on Form S-8 relating to F.N.B. Corporation 1996
          Stock Option Plan (File #333-03489).

     4)   Registration Statement on Form S-8 relating to F.N.B. Corporation
          Restricted Stock and Incentive Bonus Plan (File #333-03493).

     5)   Registration Statement on Form S-8 relating to F.N.B. Corporation
          Directors Compensation Plan (File #333-03495).

     6)   Registration Statement on Form S-8 relating to F.N.B. Corporation
          401(k) Plan (File #333-03503).

     7)   Post-Effective Amendment No. 1 on Form S-8 to Registration Statement
          on Form S-4 (File #333-01997).

     8)   Post-Effective Amendment No. 1 on Form S-8 to Registration Statement
          on Form S-4 (File #333-22909).

     9)   Registration Statement on Form S-3 relating to the F.N.B. Corporation
          Subordinated Notes and Daily Cash Accounts (File #333-74737).

    10)   Post-Effective Amendment No. 1 to Form S-3 relating to the F.N.B.
          Corporation Dividend Reinvestment and Direct Stock Purchase Plan (File
          #333-46581).

    11)   Registration Statement on Form S-8 relating to stock options assumed
          in the acquisition of Mercantile Bank of Southwest Florida (File
          #333-42333).

    12)   Post-Effective Amendment No. 1 on Form S-8 to Registration Statement
          on Form S-4 (File #333-58727).

    13)   Registration Statement on Form S-3 relating to stock warrants assumed
          in the acquisitions of Southwest Banks, Inc. and West Coast Bancorp,
          Inc. (File #333-31124).

     We consent to the incorporation by reference in the above listed
Registration Statements of our report dated January 31, 2000, with respect to
the consolidated financial statements of F.N.B. Corporation and subsidiaries
incorporated by reference in this Annual Report (Form 10-K) for the year ended
December 31, 1999.

                                                        /s/ ERNST & YOUNG LLP

Pittsburgh, Pennsylvania
March 13, 2000