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                                                                    EXHIBIT 31.1

                                 CERTIFICATIONS

I, H. Douglas Chaffin, President and Chief Executive Officer of MBT Financial
Corp., certify that:

      1.    I have reviewed this quarterly report on Form 10-Q of MBT Financial
            Corp.;

      2.    Based on my knowledge, this report does not contain any untrue
            statement of a material fact or omit to state a material fact
            necessary to make the statements made, in light of the circumstances
            under which such statements were made, not misleading with respect
            to the period covered by this report;

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this report, fairly present in all material
            respects the financial condition, results of operations and cash
            flows of the registrant as of, and for, the periods presented in
            this report;

      4.    The registrant's other certifying officer(s) and I are responsible
            for establishing and maintaining disclosure controls and procedures
            (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
            registrant and have:

                  (a)   Designed such disclosure controls and procedures, or
                  caused such disclosure controls and procedures to be designed
                  under our supervision, to ensure that material information
                  relating to the registrant, including its consolidated
                  subsidiaries, is made known to us by others within those
                  entities, particularly during the period in which this report
                  is being prepared;

                  (b)   [THIS PARAGRAPH INTENTIONALLY LEFT BLANK.]

                  (c)   Evaluated the effectiveness of the registrant's
                  disclosure controls and procedures and presented in this
                  report our conclusions about the effectiveness of the
                  disclosure controls and procedures, as of the end of the
                  period covered by this report based on such evaluation; and

                  (d)   Disclosed in this report any change in the registrant's
                  internal control over financial reporting that occurred during
                  the registrant's most recent fiscal quarter (the registrant's
                  fourth fiscal quarter in the case of an annual report) that
                  has materially affected, or is reasonably likely to materially
                  affect, the registrant's internal control over financial
                  reporting; and

      5.    The registrant's other certifying officer(s) and I have disclosed,
            based on our most recent evaluation of internal control over
            financial reporting, to the registrant's auditors and the audit
            committee of the registrant's board of directors (or persons
            performing the equivalent functions):

                  (a)   All significant deficiencies and material weaknesses in
                  the design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize and report
                  financial information; and

                  (b)   Any fraud, whether or not material, that involves
                  management or other employees who have a significant role in
                  the registrant's internal control over financial reporting.

      Date: November 5, 2004               /s/ H. Douglas Chaffin
                                           -----------------------------------
                                           H. Douglas Chaffin
                                           President and Chief Executive Officer