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                                  Exhibit 31.1

                Certification pursuant to 18 U.S.C. Section 1350
    as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 and
              pursuant to Rule 13a-14(a) and Rule 15d-14 under the
                        Securities Exchange Act of 1934


I, Robert C. Brehm, Chief Executive Officer of the Company certify that:

I have reviewed this quarterly report on Form 10-QSB of US MICROBICS INC.;

1. 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;

2. 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;

3. 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 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) 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;

         (c) Evaluated the effectiveness of the 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 Issuer's internal
control over financial reporting that occurred during the Issuer's fourth fiscal
quarter ending September 30, 2004 that has materially affected, or is reasonably
likely to materially affect, the Issuer's internal control over financial
reporting.

4. The registrant's other certifying officer(s) and I have disclosed, based on
our most recent evaluation of internal control over financial reporting, to the
registrant's auditor and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):

         (a) All 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.


Dated: August 22, 2005

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


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