1 EXHIBIT 21 LIST OF SUBSIDIARIES OF CAPSTEAD MORTGAGE CORPORATION At December 31, 1997 the subsidiaries of Capstead Mortgage Corporation were as follows: STATE OF DOMICILE -------- PARENT COMPANY SUBSIDIARY Capstead Mortgage Corporation ("CMC")................................................... Maryland Capstead Advisers, Inc............................................................... Nevada Capstead Capital Corporation......................................................... Delaware Capstead Select Corporation.......................................................... Delaware Capstead Securities Corporation I.................................................... Delaware Capstead Securities Corporation II................................................... Delaware Capstead Securities Corporation III.................................................. Delaware Capstead Securities Corporation IV................................................... Delaware CMC Securities Corporation I......................................................... Nevada CMC Securities Corporation III....................................................... Delaware CMC Securities Corporation IV........................................................ Delaware CMC ARM Securities Corporation....................................................... Delaware Capstead Mortgage Services Corporation............................................... Delaware Capstead Holdings, Inc.(1)........................................................... Delaware Capstead Inc.(2)................................................................... Delaware CMC Securities Corporation II(2)................................................... Delaware CMC Investment Partnership(3)........................................................... Texas (1) CMC owns all of the issued and outstanding preferred stock. (2) Capstead Holdings, Inc. owns all the issued and outstanding common stock. (3) A general partnership owned by CMC and Capstead Holdings, Inc.