Rule 424(b)(3)
                               File No. 333-06127



                            MDU Resources Group, Inc.

                         Automatic Dividend Reinvestment

                             and Stock Purchase Plan

                  Supplement to Prospectus Dated August 1, 1996



Adoption of New Rights Plan


         On November 12, 1998, the Board of Directors  adopted a new rights plan
that replaces the previous  rights plan which expired on November 18, 1998.  The
Board  declared  a  dividend  of one  preference  share  purchase  right on each
outstanding  share of common stock.  The dividend is payable on December 1, 1998
to  stockholders  of record on that date.  Each right  entitles  the  registered
holder of Common Stock to purchase from the Company for $125 one  one-thousandth
of a share of Series B Preference Stock, subject to adjustment.

         The terms of the rights are contained in the Rights Agreement, dated as
of November 12, 1998, between the Company and Norwest Bank Minnesota,  N.A., the
Rights Agent,  and the  Registration  Statement on Form 8-A,  dated November 12,
1998, which is incorporated by reference into the prospectus.

November 30, 1998.