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                                                                   Exhibit 31.1

                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
            PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Robert C. Brehm, certify that:

         1. I have reviewed this quarterly report on Form 10-QSB of U.S.
Microbics, 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 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 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) 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

                  c) 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 (the small business issuer's fourth fiscal quarter in
                  the case of an annual report) 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 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.


Date: May 26, 2004


                                                 /s/ Robert C. Brehm
                                                 ---------------------------
                                                     Robert C. Brehm
                                                     Chief Executive Officer