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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, Thomas A. Ritter, President and 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, 2007 (the "Report"):

1.

The Report 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, 2007.

Date: March 14, 2008 By: /s/  THOMAS A. RITTER 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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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