Exhibit 31.1

# Certification of
Principal Executive OfficerPursuant to Rule 13a-14(a) ofSecurities Exchange Act
of 1934

I, William P. Hales, the principal
executive officer of Hemagen Diagnostics Inc, certify that:

| | 1. | I have reviewed this quarterly report on Form 10-QSB of Hemagen Diagnostics,
               Inc;
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| | 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;
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| | 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;
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| | 4. | The small business issuer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 small business issuer and
               we have:
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| | 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;
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| | b. | Designed such internal control over financial reporting, or caused such internal
          control over financial reporting to be designed under our supervision, to
          provide reasonable assurance regarding the reliability of financial reporting
          and the preparation of financial statements for external purposes in accordance
          with generally accepted accounting principles;
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| | 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
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| | 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
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| | 5. | The small business issuers other certifying officer 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):
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| | 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
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| | 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.
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|Date:  February 14, 2006 |  | /s/William P. Hales
William P. HalesPresident and Chief Executive Officer
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