EXHIBIT 5.1









                                                      July 27, 2000

                                                         03-020-018


COMARCO, Inc.
2 Cromwell
Irvine, California  92618

Ladies and Gentlemen:

                    You have  requested  our  opinion  with  respect  to 200,000
shares of the  Common  Stock (the  "Shares")  of  COMARCO,  Inc.,  a  California
corporation (the "Company"),  which Shares are to be issued upon the exercise of
stock options (the "Options") granted and to be granted pursuant to the terms of
the  Company's  1995  Employee  Stock Option Plan (as  restated  June 2000) (the
"Restated Plan"). The Shares are the subject of a Registration Statement on Form
S-8 (the  "Registration  Statement"),  to which this  opinion is  attached as an
exhibit,  to be filed with the  Securities  and  Exchange  Commission  under the
Securities Act of 1933, as amended.

                    We  have  examined  the  Company's   Restated   Articles  of
Incorporation,  Bylaws and the Restated  Plan. We have also examined the records
of corporate  proceedings  taken in connection with the adoption of the Restated
Plan.

                    Based  upon  the   foregoing   examinations   and  upon  the
applicable  laws,  we are of the opinion that the shares of Common  Stock,  when
offered, sold and paid for pursuant to the exercise of options granted under the
Restated  Plan,  will  be  duly  authorized,  validly  issued,  fully  paid  and
non-assessable.

                    We hereby  consent to the use of this  opinion as an exhibit
to the Registration Statement.

                                                Very truly yours,

                                                 /s/ RIORDAN & McKINZIE