Exhibit 5.1

                           OPINION OF COOLEY GODWARD

                       [LETTERHEAD OF COOLEY GODWARD LLP]

March 16, 2000

BEI Medical Systems Company, Inc.
100 Hollister Road
Teterboro, NJ 07608

Ladies and Gentlemen:

You have requested our opinion with respect to certain matters in connection
with the filing by BEI Medical Systems Company, Inc., a Delaware corporation
(the "Company"), of a Registration Statement on Form S-3 (the "Registration
Statement") with the Securities and Exchange Commission (the "Commission") on
March 16, 2000 under the Securities Act of 1933, as amended (the "Securities
Act"). The Registration Statement relates to the registration under the
Securities Act of the resale by the holders thereof of 2,228,970 shares of the
Company's Common Stock (the "Common Shares") issuable upon the conversion of
1,114,485 shares of the Company's Series A Convertible Preferred Stock (the
"Preferred Shares").

In connection with this opinion, we have examined and relied upon the
Registration Statement and related Prospectus included therein, the Company's
Restated Certificate of Incorporation, as amended, Bylaws, as amended, and the
originals or copies certified to our satisfaction of such records, documents,
certificates, memoranda and other instruments as in our judgment are necessary
or appropriate to enable us to render the opinion expressed below. We have
assumed the genuineness and authenticity of all documents submitted to us as
originals, and the conformity to originals of all documents where due execution
and delivery are a prerequisite to the effectiveness thereof.

On the basis of the foregoing, and in reliance thereon, we are of the opinion
that:

      The Common Shares issuable upon conversion of the Preferred Shares have
been duly authorized by the Company and such Common Shares, when issued upon
conversion of the Preferred Shares in accordance with the terms of the Preferred
Shares, will be validly issued, fully paid and nonassessable.

We consent to the reference to our firm under the caption "Legal Matters" in the
Prospectus included in the Registration Statement and to the filing of this
opinion as an exhibit to the Registration Statement.

Very truly yours,

COOLEY GODWARD LLP


By:  /s/ Christopher A. Westover
   -------------------------------
       Christopher A. Westover