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                                                                     EXHIBIT 5.1

                       [NEUMAN & DRENNEN, LLC LETTERHEAD]


                                 April 30, 2001


Cell Robotics International, Inc.
2715 Broadbent Parkway N.E.
Albuquerque, New Mexico 87107

         RE:      S.E.C. REGISTRATION STATEMENT ON FORM SB-2
                  REGISTRATION NO. 33-80347; POST EFFECTIVE AMENDMENT NO. 7
                  REGISTRATION NO. 333-40895; POST EFFECTIVE AMENDMENT NO. 5
                  REGISTRATION NO. 333-55951; POST EFFECTIVE AMENDMENT NO. 2
                  REGISTRATION NO. 333-89225; POST EFFECTIVE AMENDMENT NO. 2
                  REGISTRATION NO. 333-40920; POST EFFECTIVE AMENDMENT NO. 1

Ladies and Gentlemen:

We have acted as legal counsel for Cell Robotics International, Inc. (the
"Company") in connection with the Company's Post Effective Amendments to the
Registration Statements on Form SB-2 identified above (the "Registration
Statement") filed by the Company with the Securities and Exchange Commission
under the Securities Act of 1933, as amended, and the Prospectus included as a
part of the Registration Statement (the "Prospectus"), relating to 2,972,251
shares of Common Stock of the Company (the "Common Stock") and 297,576
Redeemable Common Stock Purchase Warrants of the Company (the "Redeemable
Warrants"). The Common Stock and Redeemable Warrants may be offered and sold by
the Company and/or by certain selling securityholders of the Company in the
manner set forth in the Registration Statement and Prospectus.

In connection therewith, we have examined: (a) the Registration Statement and
the Prospectus included therein, as amended; (b) the Articles of Incorporation
and Bylaws of the Company; and (c) the relevant corporate proceedings of the
Company. In addition to such examination we have reviewed such other
proceedings, documents, and records and have ascertained or verified such
additional facts as we deem necessary or appropriate for purposes of this
opinion.

Based upon the foregoing, we are of the opinion that:

         1.       The Company has been legally incorporated and is validly
                  existing and in good standing under the laws of the State of
                  Colorado.

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         2.       The shares of Common Stock offered for resale by the Selling
                  Securityholders either (i) have been validly and lawfully
                  issued and are fully paid and nonassessable securities of the
                  Company or (ii) will, upon proper exercise of outstanding
                  stock options or Common Stock Purchase Warrants and payment
                  therefor as more fully described in the Registration Statement
                  and Prospectus be validly and lawfully issued, fully paid and
                  nonassessable securities of the Company.

         3.       The Redeemable Warrants offered for resale by the Selling
                  Securityholders have been validly and lawfully issued and are
                  fully paid and nonassessable securities of the Company.

         4.       The Common Stock and Redeemable Warrants issuable by the
                  Company upon exercise of the Representative Warrants will,
                  upon proper exercise of the Representative Warrants and
                  payment therefor as more fully described in the Registration
                  Statement and Prospectus, be validly and lawfully issued,
                  fully paid and nonassessable securities of the Company.

         5.       The Common Stock issuable upon exercise of the Redeemable
                  Warrants will, upon proper exercise of the Redeemable Warrants
                  and payment therefor as more fully described in the
                  Registration Statement and Prospectus, be validly and lawfully
                  issued, fully paid and nonassessable securities of the
                  Company.

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the caption "Legal
Matters" in the Prospectus. In giving this consent, we do not admit that we come
within the category of persons whose consent is required under Section 7 of the
Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission thereunder.

                                     Very truly yours,


                                     NEUMAN & DRENNEN, LLC