EXHIBIT
        31.1
 
 CERTIFICATION
  I,
        Lawrence A. Siebert, certify that:
  1.  I
        have
        reviewed this annual report on Form 10-KSB of Chembio Diagnostics, 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 registrant as of, and for, the
        periods presented in this report;
  4.  The
        registrant's other certifying officer 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.  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
  c.  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 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:
        March 28, 2007
 
 /s
        /
        Lawrence A. Siebert
 Lawrence
        A. Siebert
 Chief
        Executive Officer, President, and Chairman
 (Principal
        Executive Officer)