SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                             -----------------------

                                    FORM 8-K


                                 CURRENT REPORT


                       Pursuant to Section 13 or 15(d) of
                       the Securities Exchange Act of 1934

                             -----------------------


                      Date of Report
                      (Date of earliest
                      event reported):        January 20, 1999


                          Interstate Energy Corporation
             (Exact name of registrant as specified in its charter)


   Wisconsin                       1-9894                        39-1380265
(State or other               (Commission File                 (IRS Employer
jurisdiction of                    Number)                  Identification No.)
incorporation)


              222 West Washington Avenue, Madison, Wisconsin 53703
          (Address of principal executive offices, including zip code)


                                 (608) 252-3311
                         (Registrant's telephone number)






Item 5.  Other Events.

         On January  20,  1999,  the Board of  Directors  of  Interstate  Energy
Corporation (the "Company")  adopted a series of amendments to the Bylaws of the
Company (the "Bylaws"). Among other things, the amendments to the Bylaws provide
(i) procedures for shareowners to call a special meeting; (ii) discretion to the
Board  of  Directors  in  postponing  shareowner  meetings,   including  special
meetings;  (iii) procedures for adjourning a shareowner  meeting with or without
shareowner action;  (iv) requirements for raising matters that can be considered
at any annual meeting of  shareowners;  and (v)  procedures  for  shareowners to
nominate  persons for election to the Board of Directors.  These  amendments are
intended to protect  shareowners from actions being taken at shareowner meetings
without  adequate  deliberation  and to assist the Company in dealing  with such
actions in an organized manner.

         The  1999  Annual  Meeting  of  Shareowners  of the  Company  has  been
scheduled for May 19, 1999. A shareowner who intends to present  business at the
1999 Annual Meeting of Shareowners  (including,  nominating persons for election
as directors) must comply with the requirements  set forth in the Bylaws.  Among
other things, to bring business before an annual meeting, a shareowner must give
written notice thereof, complying with the Bylaws, to the Corporate Secretary of
the Company within a specified time period. Accordingly, if the Company does not
receive  notice of a shareowner  proposal  submitted  otherwise than pursuant to
Rule 14a-8 under the Securities Exchange Act of 1934, as amended, prior to March
10, 1999,  then the notice will be considered  untimely and the Company will not
be required to present such proposal at the 1999 Annual Meeting of  Shareowners.
If the Board of Directors  chooses to present  such  proposal at the 1999 Annual
Meeting of Shareowners, then the persons named in proxies solicited by the Board
of  Directors  for  the  1999  Annual  Meeting  of   Shareowners   may  exercise
discretionary voting power with respect to such proposal.

         The  amendments to the Bylaws and the Bylaws of the Company,  effective
as of  January  20,  1999,  are  attached  hereto  as  exhibits.  The  foregoing
description  of the amendments to the Bylaws does not purport to be complete and
is qualified in its entirety by reference to such exhibits.

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Item 7.  Financial Statements and Exhibits.

         (a) Not applicable.

         (b) Not applicable.

         (c) Exhibits. The following exhibit is being filed herewith:


                  (99.1)   Amendment   to  the  Bylaws  of   Interstate   Energy
                           Corporation.

                  (99.2)   Bylaws of Interstate Energy Corporation, effective as
                           of January 20, 1999.

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                                   SIGNATURES

         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
the  registrant  has duly  caused  this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                   INTERSTATE ENERGY CORPORATION



Date:  January 20, 1999            By:  /s/ Edward M. Gleason                  
                                        ---------------------------------------
                                        Edward M. Gleason
                                        Vice President, Treasurer and Corporate
                                             Secretary

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                          INTERSTATE ENERGY CORPORATION

                   Exhibit Index to Current Report on Form 8-K
                             Dated January 20, 1999


Exhibit
Number

(99.1)   Amendment to the Bylaws of Interstate Energy Corporation.

(99.2)   Bylaws of Interstate  Energy  Corporation,  effective as of January 20,
         1999.


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