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                                                                    EXHIBIT 31.1

                                  CERTIFICATION

I, Mason N. Carter, certify that:

1.   I have reviewed this quarterly report on Form 10-QSB of Merrimac
     Industries, Inc.;

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 small business issuer as of, and for, the periods presented in this
     report;

4.   The small business issuer'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 small business issuer 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 small
         business issuer, 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) [Omitted pursuant to SEC Release Nos. 33-8238 and 34-47986]

     (c) Evaluated the effectiveness of the small business issuer'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 small business issuer's
         internal control over financial reporting that occurred during the
         small business issuer's most recent fiscal quarter that has materially
         affected, or is reasonably likely to materially affect, the small
         business issuer's internal control over financial reporting; and

5.   The small business issuer's other certifying officer(s) and I have
     disclosed, based on our most recent evaluation of internal control over
     financial reporting, to the small business issuer's auditors and the audit
     committee of the small business issuer'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 small business issuer'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 small business issuer's
         internal control over financial reporting.

November 12, 2003

/s/ Mason N. Carter
Chairman, President
and Chief Executive Officer