Exhibit 5.1
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Ancor Communications, Incorporated
6130 Blue Circle Drive
Minnetonka, MN 55343

     Re:  Registration Statement on Form S-8

Ladies and Gentlemen:

      We have acted as counsel to Ancor Communications, Incorporated, a
Minnesota corporation (the "Company"), in connection with a Registration
Statement on Form S-8 relating to the sale by the Company from time to time of
up to 300,000 shares of Common Stock, $.01 par value per share, of the Company
(the "Shares") issuable under the Company's 1995 Employee Stock Purchase Plan
(the "Plan").

      We have examined such documents and have reviewed such questions of law as
we have considered necessary and appropriate for the purposes of the opinions
set forth below.

      In rendering our opinions set forth below, we have assumed the
authenticity of all documents submitted to us as originals, the genuineness of
all signatures and the conformity to authentic originals of all documents
submitted to us as copies. We have also assumed the legal capacity for all
purposes relevant hereto of all natural persons and, with respect to all parties
to agreements or instruments relevant hereto other than the Company, that such
parties had the requisite power and authority (corporate or otherwise) to
execute, deliver and perform such agreements or instruments, that such
agreements or instruments have been duly authorized by all requisite action
(corporate or otherwise), executed and delivered by such parties and that such
agreements or instruments are the valid, binding and enforceable obligations of
such parties. As to questions of fact material to our opinions, we have relied
upon certificates of officers of the Company and of public officials.

      Based on the foregoing, we are of the opinion that the Shares have been
duly authorized and, upon issuance, delivery and payment therefor in accordance
with the terms of the Plan, will be validly issued, fully paid and
nonassessable.

      Our opinions expressed above are limited to the laws of the State of
Minnesota.

      We hereby consent to the filing of this opinion as an exhibit to the
above-described Registration Statement.

Dated: January 13, 1999

                                                    Very truly yours,

                                                    /s/ Dorsey & Whitney

AEA