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                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C.  20549

                                   FORM 10-Q

   X    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES
 -----                                                                    
        EXCHANGE ACT OF 1934

FOR THE QUARTERLY PERIOD ENDED:  JUNE 30, 1997

                                       OR

        TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
------
        SECURITIES EXCHANGE ACT OF 1934

FOR THE TRANSITION PERIOD FROM ____________ TO ______________

COMMISSION FILE NUMBER:  33-5539

                          CMC SECURITIES CORPORATION I
             (Exact name of Registrant as specified in its Charter)

                  NEVADA                        75-2449544
         (State or other jurisdiction of      (I.R.S. Employer
         incorporation or organization)       Identification No.)


         2711 NORTH HASKELL, DALLAS, TEXAS           75204
      (Address of principal executive offices)     (Zip Code)

       Registrant's telephone number, including area code (214) 874-2323

The Registrant meets the conditions set forth in General Instruction H(1)(a) and
(b) for Form 10-Q and is therefore filing this Form under the reduced disclosure
format.

Indicate by check mark whether the Registrant (1) has filed all documents and
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 requirements for the past 90 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 last practicable date.
 
Common Stock ($1.00 par value)                    10,000 as of August 1, 1997

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                          CMC SECURITIES CORPORATION I
                                   FORM 10-Q
                      FOR THE QUARTER ENDED JUNE 30, 1997


                                     INDEX


                                                                     PAGE
                                                                     ----

                        PART I. -- FINANCIAL INFORMATION

 
ITEM 1. Financial Statements
 
 Balance Sheet -- June 30, 1997 and December 31, 1996................ 1
 
 Statement of Operations -- Quarter and Six Months Ended
  June 30, 1997 and 1996............................................  2
 
 Statement of Cash Flows -- Six Months Ended June 30, 1997 and 1996.. 3
 
 Notes to Financial Statements......................................  4
 
ITEM 2. Management's Discussion and Analysis of
        Financial Condition and Results of Operations...............  6
 

                          PART II. -- OTHER INFORMATION


ITEM 6. Exhibits and Reports on Form 8-K............................  6


SIGNATURES..........................................................  7
<PAGE>
 
                        PART I. -- FINANCIAL INFORMATION
                          CMC SECURITIES CORPORATION I
                                 BALANCE SHEET
                    (IN THOUSANDS, EXCEPT PER SHARE AMOUNTS)



ITEM 1. FINANCIAL STATEMENTS
<TABLE>
<CAPTION>
                                       JUNE 30, 1997   DECEMBER 31, 1996
                                       --------------  ------------------
                                        (UNAUDITED)
<S>                                    <C>             <C>
ASSETS
 Mortgage securities collateral             $609,269        $647,407
 Cash and cash equivalents                         1               1
                                            --------        --------
                                            $609,270        $647,408
                                            ========        ========
                                                           
                                                           
LIABILITIES                                                
 Collateralized mortgage securities         $609,269        $647,407
 Accrued expenses                                 35              30
                                            --------        --------
                                             609,304         647,437
                                            --------        --------
                                                           
STOCKHOLDER'S EQUITY                                       
 Common stock - $1 par value,                              
  10,000 shares authorized,                                
  issued and outstanding                          10              10
 Paid-in capital                                  81              72
 Accumulated deficit                            (125)           (111)
                                            --------        --------
                                                 (34)            (29)
                                            --------        --------
                                            $609,270        $647,408
                                            ========        ========
</TABLE>
See accompanying notes to financial statements.

                                      -1-
<PAGE>
 
                          CMC SECURITIES CORPORATION I
                            STATEMENT OF OPERATIONS
                                  (UNAUDITED)
                                 (IN THOUSANDS)


<TABLE>
<CAPTION>
                                        QUARTER ENDED      SIX MONTHS ENDED
                                           JUNE 30             JUNE 30
                                      ------------------  ------------------
                                        1997      1996      1997      1996
                                      --------  --------  --------  --------
<S>                                   <C>       <C>       <C>       <C>
Interest income on mortgage
 securities collateral                $11,555   $12,949   $23,450   $26,390
 
Interest expense on collateralized
 mortgage securities                   11,181    12,534    22,700    25,547
                                      -------   -------   -------   -------
 
   Net interest income                    374       415       750       843
                                      -------   -------   -------   -------
 
Other expenses:
 Management fees                            2         2         5         5
 Professional fees and other                9         2         9         9
 Pool insurance                           374       415       750       843
                                      -------   -------   -------   -------
 
  Total other expenses                    385       419       764       857
                                      -------   -------   -------   -------
 
Net loss                              $   (11)  $    (4)  $   (14)  $   (14)
                                      =======   =======   =======   =======
</TABLE>

See accompanying notes to financial statements.

                                      -2-
<PAGE>
 
                          CMC SECURITIES CORPORATION I
                            STATEMENT OF CASH FLOWS
                                  (UNAUDITED)
                                 (IN THOUSANDS)


<TABLE>
<CAPTION>
 
                                              SIX MONTHS ENDED JUNE 30
                                             --------------------------
                                                 1997          1996
                                             ------------  ------------
<S>                                          <C>           <C>
 
OPERATING ACTIVITIES:
 Net loss                                     $    (14)     $    (14)
 Noncash item - amortization of               
  discount and premium                             (18)          (18)
 Net change in other assets and               
  accrued expenses                                   5             5
                                              --------      --------
     Net cash used by                         
      operating activities                         (27)          (27)
                                              --------      --------
                                              
INVESTING ACTIVITIES:                         
 Mortgage securities collateral:              
  Principal collections on collateral           37,763        40,178
  Decrease in accrued interest receivable          232           250
  Decrease in short-term investments                 3             3
                                              --------      --------
     Net cash provided by                     
      investing activities                      37,998        40,431
                                              --------      --------
                                              
FINANCING ACTIVITIES:                         
 Collateralized mortgage securities:          
  Principal payments on securities             (37,763)      (40,178)
  Decrease in accrued interest payable            (217)         (235)
 Capital contributions                               9             9
                                              --------      --------
     Net cash used by financing               
      activities                               (37,971)      (40,404)
                                              --------      --------
                                              
Net change in cash and cash equivalents              -             -
                                              
Cash and cash equivalents at beginning        
 of period                                           1             1
                                              --------      --------
                                              
Cash and cash equivalents at end of           
 period                                       $      1      $      1
                                              ========      ========
 </TABLE>

See accompanying notes to financial statements.

                                      -3-
<PAGE>
 
                          CMC SECURITIES CORPORATION I
                         NOTES TO FINANCIAL STATEMENTS
                                 JUNE 30, 1997
                                  (UNAUDITED)



NOTE A -- BASIS OF PRESENTATION

The accompanying unaudited financial statements have been prepared in accordance
with generally accepted accounting principles for interim financial information
and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X.
Accordingly, they do not include all of the information and footnotes required
by generally accepted accounting principles for complete financial statements.
In the opinion of management, all adjustments (consisting of normal recurring
accruals) considered necessary for a fair presentation have been included.
Operating results for the quarter and six months ended June 30, 1997 are not
necessarily indicative of the results that may be expected for the calendar year
ending December 31, 1997.  For further information refer to the financial
statements and footnotes thereto included in the CMC Securities Corporation I
annual report on Form 10-K for the period ended December 31, 1996.

NOTE B -- DISCLOSURES EGARDING FAIR VALUES OF MORTGAGE SECURITIES COLLATERAL

The estimated fair values of mortgage securities collateral have been determined
by using available market information and appropriate valuation methodologies;
however, considerable judgment is required in interpreting market data to
develop these estimates.  In addition, fair values fluctuate on a daily basis.
Accordingly, the estimates presented herein are not necessarily indicative of
the amounts that could be realized in a current market exchange.  The use of
different market assumptions and/or estimation methodologies may have a material
effect on the estimated fair value amounts.

The fair values of mortgage securities collateral were estimated using quoted
market prices, when available, including quotes made by Capstead Mortgage
Corporation's lenders in connection with designating collateral for repurchase
arrangements.

The following table summarizes the fair values of mortgage securities collateral
(in thousands):

<TABLE>
<CAPTION>
                          JUNE 30, 1997   DECEMBER 31, 1996
                          --------------  ------------------
<S>                       <C>             <C>
     Carrying amount         $609,269         $647,407
     Unrealized gains           9,505            5,620
     Unrealized losses         (2,930)          (7,865)
                             --------         --------
                                             
      Fair value             $615,844         $645,162
                             ========         ========
</TABLE>

All mortgage securities collateral is held-to-maturity.  The maturity of
mortgage securities collateral is directly affected by the rate of principal
prepayments by mortgagors.  In addition, upon the redemption of remaining bonds
outstanding pursuant to clean-up calls, released collateral may be sold.  Such
sales are deemed maturities under the provisions of Statement of Financial
Accounting Standards No. 115.  No such redemptions occurred during the six
months ended June 30, 1997 or 1996.

                                      -4-
<PAGE>
 
NOTE C -- NET INTEREST INCOME ANALYSIS

The following table summarizes interest income and interest expense and the
average effective interest rates for the periods indicated (dollars in
thousands):

<TABLE>
<CAPTION>
                                                          QUARTER ENDED JUNE 30
                                                  -------------------------------------
                                                         1997              1996
                                                  -----------------  ------------------
                                                              AVERAGE          AVERAGE
                                                    AMOUNT     RATE    AMOUNT    RATE
                                                   --------   -------  -------  -------
<S>                                                <C>        <C>     <C>      <C>
Interest income on mortgage                                 
 securities collateral                              $11,555    7.52%   $12,949   7.56%
Interest expense on                                                              
 collateralized mortgage securities                  11,181    7.28     12,534   7.32
                                                    -------            -------   
Net interest income                                 $   374            $   415   
                                                    =======            =======   

 
                                                          SIX MONTHS ENDED JUNE 30
                                                  -------------------------------------
                                                         1997              1996
                                                  -----------------  ------------------
                                                              AVERAGE           AVERAGE
                                                    AMOUNT     RATE     AMOUNT    RATE
                                                   --------   -------  -------  -------
Interest income on mortgage                                
 securities collateral                              $23,450    7.51%   $26,390   7.58%
Interest expense on                                                             
 collateralized mortgage securities                  22,700    7.27     25,547   7.34
                                                    -------            -------   
                                                                                
Net interest income                                 $   750            $   843   
                                                    =======            =======   
</TABLE>

The following table summarizes changes in interest income and interest expense
due to changes in interest rates, versus changes in volume for the quarter and
six months ended June 30, 1997, compared to the same periods in 1996 (in
thousands):

<TABLE>
<CAPTION>
                                                   QUARTER ENDED JUNE 30, 1997
                                                 ------------------------------
                                                   RATE*     VOLUME*     TOTAL
                                                 -------  ---------  ---------
<S>                                                <C>       <C>        <C>
Interest income on mortgage securities    
 collateral                                         $ (67)   $(1,327)   $(1,394)
Interest expense on collateralized        
 mortgage securities                                  (68)    (1,285)    (1,353)
                                                    -----    -------    -------
                                                    $   1    $   (42)   $   (41)
                                                    =====    =======    =======
                                          
                                                   SIX MONTHS ENDED JUNE 30, 1997
                                                   ------------------------------
                                                    RATE*    VOLUME*      TOTAL
                                                    -----    -------    -------
Interest income on mortgage securities    
 collateral                                         $(252)   $(2,688)   $(2,940)
Interest expense on collateralized        
 mortgage securities                                 (245)    (2,602)    (2,847)
                                                    -----    -------    -------
                                                    $  (7)   $   (86)   $   (93)
                                                    =====    =======    =======
</TABLE>
*  THE CHANGE IN INTEREST DUE TO BOTH VOLUME AND RATE HAS BEEN ALLOCATED
   TO VOLUME AND RATE CHANGES IN PROPORTION TO THE RELATIONSHIP OF THE
   ABSOLUTE DOLLAR AMOUNTS OF THE CHANGE IN EACH.

                                      -5-
<PAGE>
 
ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS


FINANCIAL CONDITION AND RESULTS OF OPERATIONS
---------------------------------------------

CMC Securities Corporation I (the "Company"), was incorporated in Nevada on May
7, 1986 as a special-purpose finance corporation and is a wholly-owned
subsidiary of Capstead Mortgage Corporation ("CMC").

Since inception the Company has issued approximately $1.7 billion of
collateralized mortgage obligations ("CMOs").  The Company has not retained any
investment in the CMOs issued; therefore, no related economic benefit will be
received and no related net income or loss will be recognized.  However, in
instances where an affiliate retained investments in these CMOs, the issuances
were accounted for as financings, and accordingly, the collateral and bonds are
reflected on the Company's balance sheet.  The Company has not issued any CMOs
during 1997.

The Company's net losses are due to operational costs incurred (management and
professional fees).

LIQUIDITY AND CAPITAL RESOURCES
-------------------------------

All ongoing CMO expenses of the Company are paid out of the excess cash flows on
the CMOs issued before the residual holders receive their residual interest.
The Company believes that the excess cash flows will be sufficient to pay
ongoing CMO expenses.  Cash flow requirements due to ongoing operational costs
are funded by CMC.


                          PART II. -- OTHER INFORMATION


ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K:

(a) Exhibits:

    Exhibit 27 Financial Data Schedule (electronic filing only).

(b) Reports on Form 8-K:  None.

                                      -6-
<PAGE>
 
                                   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.



                                              CMC SECURITIES CORPORATION I



Date:  August 1, 1997                  By:/s/ RONN K. LYTLE
                                          ------------------------------------
                                          Ronn K. Lytle
                                          Chairman and Chief Executive Officer



Date:  August 1, 1997                  By:/s/ ANDREW F. JACOBS
                                          ------------------------------------
                                          Andrew F. Jacobs
                                          Senior Vice President - Control
                                            and Treasurer

                                      -7-