<PAGE>   1

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                   FORM 10-Q

                   Quarterly Report under Section 13 or 15(d)
                     of the Securities Exchange Act of 1934


For Quarter Ended             March 31, 1998
                 -------------------------------------------------------------
Commission File Number     33-19863
                      --------------------------------------------------------

                   Mountain States Guaranty Mortgage Company
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             (Exact name of registrant as specified in its charter)

         Colorado                                     84-1075984
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(State of Incorporation)                    (IRS Employer Identification No.)

                621 17th Street, Suite 1900, Denver, CO   80293-0621
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             (Address and Zip Code of Principal Executive Offices)


Registrant's telephone number, including area code:        (303) 295-3000
                                                   ---------------------------
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 for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirement for the past ninety days.

Yes     X                                  No
    ---------                                 ----------


                     APPLICABLE ONLY TO CORPORATE ISSUERS:

Indicate the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practicable date.

CLASS            SHARES OUTSTANDING AT MARCH 31, 1998

Common                            1,000





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                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                                                     Page

PART I
------
<S>                                                                                                                    <C>
Item 1.  Financial Statement

                 Balance Sheets as of December 31, 1997 and
                    March 31, 1998                                                                                     3

                 Statement of Cash Flows for the Periods
                    January 1, 1996 through March 31, 1997
                    and January 1, 1998 through March 31, 1998                                                         4

                 Notes to Financial Statements                                                                         5

Item 2.  Management's Discussion and Analysis of Financial
                    Condition and Results of Operations                                                                6


PART II
-------

Item 1.  Legal Proceedings                                                                                             7

Item 2.  Changes in Securities                                                                                         7

Item 3.  Defaults Upon Senior Securities                                                                               7

Item 4.  Submission of Matters to a Vote of Security Holders                                                           7

Item 5.  Other Information                                                                                             7

Item 6.  Exhibits and Reports on Form 8-K                                                                              7

Signatures                                                                                                             8

Index to Exhibits                                                                                                      9
</TABLE>





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                   MOUNTAIN STATES GUARANTY MORTGAGE COMPANY

                                 Balance Sheets
                      December 31, 1997 and March 31, 1998
                                  (Unaudited)



                                     ASSETS

<TABLE>
<CAPTION>
                                                  1998                    1997
                                                  ----                    ----
<S>                                               <C>                     <C>
Cash                                              $1,000                  $1,000
                                                  ------                  ------

                                                  
Total Assets                                      $1,000                  $1,000
                                                  ======                  ======
</TABLE>




                              STOCKHOLDERS' EQUITY


<TABLE>
<S>                                               <C>                     <C>
Common Stock, par value $1.00 per share,
authorized 1,000,000 shares, issued and           
outstanding 1,000 shares                          $1,000                  $1,000
                                                  ------                  ------

Total stockholders' equity                        $1,000                  $1,000
                                                  ======                  ======
</TABLE>





See accompanying notes to financial statements.





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                   MOUNTAIN STATES GUARANTY MORTGAGE COMPANY

                        Statement of Cash Flows for the
                           Periods January 1, 1997 to
                     March 31, 1997 and January 1, 1998 to
                                 March 31, 1998
                                  (Unaudited)


<TABLE>
<CAPTION>
                                                                1998     1997 
                                                                -----    -----
<S>                                                             <C>      <C>
Net Proceeds from issuance of collateralized
    mortgage obligations (including accrued
    interest) and sale of residual interest in bonds            $   0    $   0

Purchase price of Certificates (including
    accrued interest)                                                0       0
                                                                ------   ------

Net Increase in Cash                                                 0       0


Cash balance at beginning of the Period                          1,000   1,000
                                                                ------   -----

Cash balance at end of the Period                               $1,000  $1,000
                                                                ======  ======
</TABLE>





See accompanying notes to financial statements.





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                   MOUNTAIN STATES GUARANTY MORTGAGE COMPANY

                         NOTES TO FINANCIAL STATEMENTS

NOTE 1 - ORGANIZATION AND OPERATIONS

Mountain States Guaranty Mortgage Company (the "Company") is a limited purpose
corporation established under the laws of Colorado on January 22, 1988.  The
Company was organized for the purpose of issuing collateralized mortgage
obligations (the "Bonds") secured by mortgage-backed certificates (the
"Certificates").  Bonds issued are obligations solely of the Company.

NOTE 2 - COLLATERALIZED MORTGAGE OBLIGATIONS

On July 28, 1988, the Company issued Bonds in the aggregate principal amount of
$20,000,000.  The principal amounts outstanding at March 31, 1998, the interest
rates and the stated maturities of the Bonds are as follows:

<TABLE>
<CAPTION>
      CLASS               PRINCIPAL AMOUNT                   INTEREST RATE                  STATED MATURITY
      -----               ----------------                   -------------                  ---------------
       <S>                    <C>                            <C>                            <C>
       I-D                      $148,000                         9.40                         04/01/2016
       I-F                     1,982,000                         9.40                         08/01/2018
       I-G                     1,378,000                         9.40                         08/01/2018
                              ----------                                                           
                              $3,508,000
                              ==========
</TABLE>                  

The Series One Bonds are collateralized by Certificates having annual pass-
through rates of 9.5%.  The par value of the Certificates outstanding at March
31, 1998, is $3,341,000.

On March 28, 1989, the Company issued Bonds in the aggregate principal amount
of $20,000,000.  The principal amounts outstanding at June 30, 1997, the
interest rates and the stated maturities of the Bonds are as follows:

<TABLE>
<CAPTION>
      CLASS               PRINCIPAL AMOUNT                   INTEREST RATE           STATED MATURITY
      -----               ----------------                   -------------           ---------------
       <S>                <C>                               <C>                     <C>
       II-D                  $  433,000                        10.45                      03/01/2017
       II-E                   2,025,000                        10.40                      04/01/2019
       II-F                      14,000                        10.45                      04/01/2019
                             ----------                                                         
                             $2,472,000                                              
                             ==========
</TABLE>                     

The Series Two Bonds are collateralized by Certificates having annual pass-
through rates of 10.5%.  The par value of the Certificates outstanding at March
31, 1998, is $2,440,000.

The issuance of Series One and Two Bonds and related residual interests, and
the respective simultaneous delivery of the Certificates to State Street Bank
and Trust Company (the "Trustee) for the benefit of the Bondholders has been
accounted for as a sale of the Certificates, and the transaction resulted in no
gain or loss to the Company.  Accordingly, no statement of operations is




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presented and the Bonds and the related Certificates do not appear in the
accompanying balance sheets.

Coughlin  & Company, Inc., an entity which has common ownership with the
Company, served as Underwriter for these issuances.  Another entity having the
same owners purchased the residual interest in the collateral securing the
Bonds.

NOTE 3 - CERTIFICATES HELD BY TRUSTEE

As required by the Indenture relating to the Bonds, the Certificates securing
the Bonds are held as collateral by the Trustee.  The Trustee collects
principal and interest payments on the Certificates and makes principal and
interest payments on the Bonds using a collection account, including
reinvestment earnings thereon, established for the Bonds.

NOTE 4 - INCOME TAXES

The Company has elected to treat each issuance as a real estate mortgage
investment conduit for federal income tax purposes.  Accordingly, the Company
does not report any income or loss.  Therefore, no provision for income taxes
has been made in the accompanying financial statements


ITEM 2.  MANAGEMENT'S DISCUSSIONS AND ANALYSIS OF FINANCIAL CONDITION AND
RESULTS OF OPERATIONS.

General

Mountain States Guaranty Mortgage Company is a corporation established under
the laws of Colorado on January 12, 1988.  The Company was created for the sole
purpose of the issuance and sale of collateralized mortgage obligations (the
"Bonds") secured by mortgage-backed certificates (the "Certificates").  The
Bonds represent obligations solely of the Company.

Capital Resources and Liquidity

The Company's sources of funds with respect to the payment of Bonds are
receipts of principal and interest payments on the related Certificates.  It is
anticipated that payments of principal and interest on the Certificates
collateralizing the Bonds will provide sufficient funds for the payment of all
fees and expenses, including amounts necessary to make principal and interest
payments on the Bonds, and to retire the Bonds not later than their respective
stated maturities.

Results of Operations

For the period ended March 31, 1998, the Company did not recognize any gains on
issuance of Bonds.  Any excess of either receipts of principal and interest on
the related Certificates or debt service payments and other fees and expenses
will revert to the residual class of bondholders in each of the Series One,
Series Two, Series Three and Series Four Bonds and not to the Company.





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                                    PART II


Item 1.  Legal Proceedings

                          None


Item 2.  Changes in Securities

                          Not Applicable


Item 3.  Defaults upon Senior Securities

                          Not Applicable


Item 4.  Submission of Matters to a Vote of Security Holders

                          Not Applicable


Item 5.  Other Information

                          Not Applicable


Item 6.  Exhibits and Reports on Form 8-K

               a)         The exhibits required by this item and incorporated
                          herein by reference are listed in the accompanying
                          index (page 1 ) to exhibits.

               b)         There were no reports on Form 8-K filed by the
                          Company during the period covered by this report.

               c)         Financial Data Schedule.


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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 thereunto duly authorized.



       Registrant:              MOUNTAIN STATES GUARANTY MORTGAGE COMPANY



                                Mountain States Guaranty Mortgage Company



Dated:

April 20, 1998  By:    /s/ Dennis F. Coughlin
                   ----------------------------------------------------
                   Name:      Dennis F. Coughlin
                   Title:     President & Chief Executive Officer



Dated:

April 20, 1998  By:    /s/ Harold C. Jones
                   ---------------------------------------------------- 
                   Name:    Harold C. Jones
                   Title:   Treasurer & Chief Financial Officer





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                               INDEX TO EXHIBITS



Pursuant to the General Rules and Regulations under the Securities Exchange Act
of 19234, as amended, the following Exhibits previously filed with the
Securities and Exchange Commission are incorporated by reference as Exhibits to
the Form 10-Q:

<TABLE>
<CAPTION>
         Exhibit No.                       Description
         -----------                       -----------
               <S>                         <C>
               1                           Indenture dated as of July 1, 1988, between the Company, and the Trustee
                                           (incorporated by reference to Exhibit 4(a) of Registrant's Form 10-Q filed
                                           with the SEC on November 11, 1988).

              27                           Financial Data Schedule
</TABLE>





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