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                                                                     Exhibit 5.1

Benesch, Friedlander, Coplan & Aronoff LLP
88 E. Broad St.
Columbus Ohio 43215


June 12, 2000

Board of Directors
Neoprobe Corporation
425 Metro Place North, Suite. 300
Dublin, Ohio 43017-1367

Gentlemen:

Neoprobe Corporation, a Delaware corporation (the "Company"), has filed with the
Securities and Exchange Commission under the Securities Act of 1933, a
Registration Statement on Form S-3 (the "Registration Statement") to register
3,000,000 shares of common stock, par value $0.001 per share (the "Shares").

You have requested our opinion in connection with the Company's filing of the
Registration Statement. In this connection, we have examined and relied upon
originals or copies, certified or otherwise identified to our satisfaction as
being true copies, of all such records of the Company, all such agreements,
certificates of officers of the Company and others, and such other documents,
certificates and corporate or other records as we have deemed necessary as a
basis for the opinion expressed in this letter, including, without limitation,
the Company's Certificate of Incorporation (the "Charter"), the Registration
Statement and the prospectus which forms a part of the Registration Statement
(the "Prospectus").

In our examination, we have assumed the genuineness of all signatures, the legal
capacity of all natural persons, the authenticity of all documents submitted to
us as originals and the conformity to authentic original documents of all
documents submitted to us as certified or photostatic copies.

We have investigated such questions of law for the purpose of rendering the
opinion in this letter as we have deemed necessary. We express no opinion in
this letter concerning any law other than the General Corporation Law of the
State of Delaware and the federal law of the United States of America.

On the basis of and in reliance on the foregoing, we are of the opinion that the
Shares have been validly issued, and are fully paid and non-assessable.

We consent to the filing of this letter as an exhibit to the Registration
Statement. 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, or the rules and regulations of the Securities and Exchange
Commission thereunder.

Very truly yours,


                                      BENESCH, FRIEDLANDER, COPLAN & ARONOFF LLP

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