Exhibit 32.1


                            CHIEF EXECUTIVE OFFICER
               CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                 SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

         Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (Section 1350
of Chapter 63 of Title 18 of the United States Code), I, [             ], Chief
Executive Officer of ACNB Corporation (the "Company"), hereby certify that, to
the best of my knowledge, the Company's Annual Report on Form 10-K for the
period ended December 31, 2004 (the "Report"):

         1.  fully complies with the requirements of Section 13(a) or 15(d) of
             the Securities Exchange Act of 1934; and

         2.  the information contained in the Report fairly presents, in all
             material respects, the financial condition and results of
             operations of the Company for the year ended December 31, 2004.


Date:    [               ]               By:   /s/ Thomas A. Ritter
                                               President and
                                               Chief Executive Officer




The foregoing certification is being furnished solely pursuant to Section 906 of
the Sarbanes-Oxley Act of 2002 (Section 1350 of Chapter 63 of Title 18 of the
United States Code) and is not being filed as part of the Report or as a
separate disclosure document.

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