Exhibit 23.1

            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference of our report dated February 24,
2004, except for Note 2 as to which the date is January 4, 2005, with respect to
the consolidated financial statements of F.N.B. Corporation and subsidiaries
included in this Current Report (Form 8-K) for the year ended December 31, 2003
in the following registration statements and in the related Prospectuses:

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 # 333-38372).

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 F.N.B. Corporation
      Subordinated Notes and Daily Cash Accounts (File #333-74737).

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

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

12.   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).



13.   Post-Effective Amendment No. 1 to Form S-3 relating to the F.N.B.
      Corporation Dividend Reinvestment and Direct Stock Purchase Plan (File
      #333-38374).

14.   Amendment No. 1 to Form S-3 relating to the registration of F.N.B.
      Corporation Subordinated Term Notes and Daily Notes (File #333-38370).

15.   Registration Statement on Form S-8 relating to the F.N.B. Corporation
      Salary Savings Plan (File #333-40648).

16.   Registration Statement on Form S-8 relating to the F.N.B. Corporation 1998
      Directors Stock Option Plan (File #333-38376).

17.   Registration Statement on Form S-8 relating to the F.N.B. Corporation 2001
      Incentive Plan (File #333-63042).

18.   Registration Statement on Form S-3 relating to the registration of F.N.B.
      Corporation and F.N.B. Capital Trust I commons stock, preferred stock,
      debt securities, warrants, and trust preferred securities (File
      #333-74866).

19.   Registration Statement on Form S-8 relating to the F.N.B. Corporation 1996
      Incentive Plan (File #333-83760).

20.   Registration Statement on Form S-8 relating to stock option agreements
      granted under the Promistar Financial Corporation 1998 Equity Incentive
      Plan and assumed by F.N.B. Corporation (File #333-83756).

21.   Registration Statement on Form S-8 relating to the F.N.B. Corporation
      401(k) Plan (File #333-97113).

22.   Registration Statement on Form S-8 relating to the Roger Bouchard
      Insurance, Inc. 401(k) Plan (File #333-97115).

23.   Pre-Effective Amendment No. 1 to the Registration Statement filed on Form
      S-3 related to the Dividend Reinvestment and Stock Purchase Plan (File
      #333-111833).

24.   Post-Effective Amendment No. 1 to the Registration Statement filed on Form
      S-3 related to the issuance of Subordinated Term Notes (File #333-103902).

/s/ ERNST & YOUNG LLP

Pittsburgh, Pennsylvania
January 4, 2005