Exhibit 32.2

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

      In connection with the Annual Report on Form 10-K of MASSBANK Corp. (the
"Registrant") for the year ended December 31, 2004 (the "Report") as filed with
the Securities and Exchange Commission on the date hereof, I, Reginald E.
Cormier, Sr. Vice President, Treasurer and Chief Financial Officer of the
Registrant, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002 that:

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

      2.    To my knowledge, the information contained in the Report fairly
            presents, in all material respects, the financial condition and
            results of operations of the Registrant as of and for the period
            covered by the report.

Dated: March 14, 2005

                                               /s/ Reginald E. Cormier
                                               --------------------------------
                                               Reginald E. Cormier
                                               Sr. Vice President, Treasurer
                                               Chief Financial Officer

The foregoing certification is being furnished solely pursuant to 18 U.S.C.
Section 1350 and is not being filed as part of the Report or as a separate
disclosure document.