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                                                                    EXHIBIT 31.2

                                  CERTIFICATION

            PURSUANT TO SECTION 302 OF THE SARBANES OXLEY ACT OF 2002

I, Dennis E. Valentine, certify that:

         1) I have reviewed this quarterly report on Form 10-Q of JMAR
Technologies, Inc.;

         2) Based on my knowledge, this quarterly 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
quarterly report;

         3) Based on my knowledge, the financial statements, and other financial
information included in this quarterly 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 quarterly 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 we 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 quarterly report is being prepared;

                  b) evaluated the effectiveness of the registrant's disclosure
         controls and procedures and presented in this quarterly report our
         conclusions about the effectiveness of the disclosure controls and
         procedures, as of the end of the period covered by this quarterly
         report (based on such evaluation); and

                  c) disclosed in this quarterly report any change in the
         registrant's internal control over financial reporting that occurred
         during the registrant's most recent fiscal quarter 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:

                  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.

                                      By: /s/ Dennis E. Valentine
                                          ------------------------------
                                          Dennis E. Valentine
                                          Chief Financial Officer

November 12, 2003