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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

   
                                 FORM 10-K/A-1
                     ANNUAL REPORT UNDER SECTION 13 OR 15(D)
                     OF THE SECURITIES EXCHANGE ACT OF 1934       

(Mark One)
    |X| Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange
        Act of 1934 for the year ended December 31, 1997

    |_| Transition Report Pursuant to Section 13 or 15(d) of the Securities
        Exchange Act of 1934.

Commission File Number 1-2982

                       ANCOR COMMUNICATIONS, INCORPORATED
               -------------------------------------------------
             (Exact name of registrant as specified in its charter)

            MINNESOTA                                       41-1569659
---------------------------------               --------------------------------
  (State or other jurisdiction                 (IRS Employer Identification No.)
 of incorporation or organization) 


 6130 BLUE CIRCLE DRIVE  MINNETONKA, MINNESOTA                 55343
----------------------------------------------               ---------
  (Address of principal executive offices)                   (Zip code)

        Registrant's Telephone number, including area code (612) 932-4000


           Securities registered pursuant to Section 12(b) of the Act:


       TITLE OF EACH CLASS             NAME OF EACH EXCHANGE ON WHICH REGISTERED
       --------------------            -----------------------------------------
Common Stock, par value $.01 per share           Pacific Stock Exchange

        Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or such shorter period that the registrant was required
to file such reports) and (2) has been subject to such filing requirements for
the past 90 days. Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [X]

As of March 20, 1998, the Company had 11,919,163 shares of Common Stock
outstanding. The aggregate market value of the 11,873,863 shares of Common Stock
held by non-affiliates of the Company was $65,306,246, based on the closing
share price on March 20, 1998 on the Nasdaq SmallCap Market.

Documents incorporated by reference: Certain responses to Part III are
incorporated herein by reference to information contained in the Company's
definitive proxy statement for its 1998 annual meeting of shareholders to be
filed with the Securities and Exchange Commission on or before April 30, 1998.


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                                   SIGNATURES
   
In accordance with Section 13 or 15(d) of the Exchange Act, the registrant
caused this amendment to no. 1 to Form 10-K to be signed on its behalf by the
undersigned, thereunto duly authorized.      

                                    ANCOR COMMUNICATIONS, INCORPORATED

                                    By /S/ Kenneth E. Hendrickson
                                       ----------------------------------
                                       Kenneth E. Hendrickson
                                       Chairman of the Board & CEO

   
Dated:  May 5, 1998
        --------------------------------

         In accordance with the Exchange Act, this report has been signed below
by the following persons on behalf of the registrant and in the capacities and
on the dates indicated. Each person whose signature to this report on Form 10-K
appears below hereby constitutes and appoints Kenneth E. Hendrickson and Steven
E. Snyder, and each of them, as his true and lawful attorney-in-fact and agent,
with full power of substitution, to sign on his behalf individually and in the
capacity state below and to perform any acts necessary to be done in order to
file all amendments to this report on Form 10-K, and any and all instruments or
documents filed as part of or in connection with this report on Form10-K or the
amendments thereto and each of the undersigned does hereby ratify and confirm
all that said attorney-in-fact and agent, or his substitutes, shall do or cause
to be done by virtue hereof.     

   
           NAME                            TITLE                    DATE
           ----                            -----                    ----
/S/KENNETH E. HENDRICKSON      Chairman, Director and CEO        May 5, 1998
---------------------------    (principal executive officer)
Kenneth E. Hendrickson         


/S/STEVEN E. SNYDER            Chief Financial Officer           May 5, 1998
---------------------------    (principal financial officer)
Steven E. Snyder                     

            *                  Director                          May 5, 1998
---------------------------
Amyl Ahola

            *                  Director                          May 5, 1998
---------------------------
Gerald M. Bestler

            *                  Director                          May 5, 1998
---------------------------
John F. Carlson

            *                  Director                          May 5, 1998
---------------------------
Thomas F. Hunt, Jr.

            *                  Director                          May 5, 1998
---------------------------
Paul Lidsky


* By /s/ Kenneth E. Hendrickson
     -----------------------------
     Kenneth E. Hendrickson             
     

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