Registration No.

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                          SECURITIES AND EXCHANGE COMMISSION
                               Washington, D.C.  20549

                                       FORM T-1

            STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939
                     OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE

CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO
SECTION 305(b)(2)
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                               WILMINGTON TRUST COMPANY
                 (Exact name of trustee as specified in its charter)


        Delaware                                      51-0055023
(State of incorporation)                 (I.R.S. employer identification no.)

                                 Rodney Square North
                               1100 North Market Street
                             Wilmington, Delaware  19890
                       (Address of principal executive offices)

                                  Cynthia L. Corliss
                           Vice President and Trust Counsel
                               Wilmington Trust Company
                                 Rodney Square North
                             Wilmington, Delaware  19890
                                    (302) 651-8516
              (Name, address and telephone number of agent for service)

                          FIRST INTERSTATE BANCSYSTEM, INC.

                 (Exact name of obligor as specified in its charter)

              Montana                                   81-0331430
       (State of incorporation)            (I.R.S. employer identification no.)

       401 North 31st Street
          Billings, Montana                               59101
(Address of principal executive offices)                (Zip Code)



                ___% Junior Subordinated Deferrable Interest Debentures
                         of First Interstate Bancsystem, Inc.
                         (Title of the indenture securities)

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ITEM 1.  GENERAL INFORMATION.

         Furnish the following information as to the trustee:

    (a)  Name and address of each examining or supervising authority
         to which it is subject.

         Federal Deposit Insurance Co.      State Bank Commissioner
         Five Penn Center                   Dover, Delaware
         Suite #2901
         Philadelphia, PA

    (b)  Whether it is authorized to exercise corporate trust powers.

         The trustee is authorized to exercise corporate trust powers.

ITEM 2.  AFFILIATIONS WITH THE OBLIGOR.

         If the obligor is an affiliate of the trustee, describe each
    affiliation:

         Based upon an examination of the books and records of the trustee and
    upon information furnished by the obligor, the obligor is not an affiliate
    of the trustee.

ITEM 3.  LIST OF EXHIBITS.

         List below all exhibits filed as part of this Statement of
    Eligibility and Qualification.

    A.   Copy of the Charter of Wilmington Trust Company, which includes the
         certificate of authority of Wilmington Trust Company to commence
         business and the authorization of Wilmington Trust Company to exercise
         corporate trust powers (incorporated by reference to Exhibit A to 
         Exhibit 25.1).
    B.   Copy of By-Laws of Wilmington Trust Company (incorporated by 
         reference to Exhibit B to Exhibit 25.1).
    C.   Consent of Wilmington Trust Company required by Section 321(b) of
         Trust Indenture Act.
    D.   Copy of most recent Report of Condition of Wilmington Trust Company 
         (incorporated by reference to Exhibit D to Exhibit 25.1).

    Pursuant to the requirements of the Trust Indenture Act of 1939, as
amended, the trustee, Wilmington Trust Company, a corporation organized and
existing under the laws of Delaware, has duly caused this Statement of
Eligibility to be signed on its behalf by the undersigned, thereunto duly
authorized, all in the City of Wilmington and State of Delaware on the 10th day
of October, 1997.



                                         WILMINGTON TRUST COMPANY
[SEAL]
                                         
Attest: /s/ W. Chris Sponenberg          By: /s/ Emmett R. Harmon
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       Assistant Secretary                  Name: Emmett R. Harmon
                                            Title:  Vice President




                                      EXHIBIT C


                                SECTION 321(b) CONSENT


    Pursuant to Section 321(b) of the Trust Indenture Act of 1939, as amended,
Wilmington Trust Company hereby consents that reports of examinations by
Federal, State, Territorial or District authorities may be furnished by such
authorities to the Securities and Exchange Commission upon requests therefor.



                                    WILMINGTON TRUST COMPANY


Dated: October 10, 1997             By: /s/ Emmett R. Harmon
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                                       Name: Emmett R. Harmon
                                       Title: Vice President