UNITED STATES
                       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): April 25, 2002

                        FIRST INTERSTATE BANCSYSTEM, INC.
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             (Exact name of registrant as specified in its charter)



             MONTANA                     33-64304                81-0331430
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(State or other jurisdiction of         (Commission             (IRS Employer
 incorporation or organization)          File No.)           Identification No.)


                      401 NORTH 31ST STREET, BILLINGS, MT
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                    (Address of principal executive offices)


                                 (406) 255-5390
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              (Registrant's telephone number, including area code)


                                 NOT APPLICABLE
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          (Former name or former address, if changed since last report)

Item 1.   Not Applicable.

Item 2.   Not Applicable.

Item 3.   Not Applicable.

Item 4.   Not Applicable.

Item 5.   Other Events and Regulation FD Disclosure.

          On April 26, 2002, First Interstate BancSystem, Inc. issued its first
          quarter 2002 performance report and shareholders' letter
          ("Shareholders' Letter") to holders of common stock of the Company as
          of April 26, 2002.

          Certain statements contained in the Shareholders' Letter constitute
          "forward-looking statements" that involve risk and uncertainties. The
          Company wishes to caution readers that the following factors, among
          others may cause the actual results, performance or achievements of
          the Company to be materially different from any future results,
          performance or achievements expressed or implied by such
          forward-looking statements. Such factors include general economic and
          business conditions in those areas in which the Company operates,
          credit quality, demographic changes, competition, fluctuations in
          interest rates, changes in business strategy or development plans and
          changes in governmental regulations. These and other risk factors are
          set forth from time to time in the Company's reports filed with the
          Securities and Exchange Commission.

          The Shareholders' Letter is attached as Exhibit 99 to the Current
          Report on Form 8-K.

Item 6.   Not Applicable.

Item 7.   Financial Statements and Exhibits.

          (a)  Not Applicable.

          (b)  Not Applicable.

          (c)  Not Applicable.

Item 8.   Not Applicable.

Item 9.   Not Applicable.

                                    SIGNATURE

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

Dated: April 25, 2002

                                               FIRST INTERSTATE BANCSYSTEM, INC.



                                               By:    /s/ THOMAS W. SCOTT
                                                   -----------------------------
                                                   Thomas W. Scott
                                                   Chief Executive Officer