**EXHIBIT
      31.1**






**Rule
      13a-14(a)/15d-14(a) Certification**






I,
      Peter
      P. Phildius, certify that:






1.     
      I have reviewed this quarterly report on Form 10-QSB of Avitar, 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(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)     
      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(s) and I
      have disclosed, based on our most recent evaluation of the 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 controls 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:
      May
      15, 2007      /S/
      Peter P. Phildius


Peter
      P.
      Phildius


Chairman
      and Chief


Executive
      Officer


(Principal
      Executive Officer)