A speech recognition interface system capable of handling a plurality of application programs simultaneously, and realizing convenient speech input and output modes which are suitable for the applications in the window systems and the speech mail systems. The system includes a speech recognition unit for carrying out a speech recognition processing for a speech input made by a user to obtain a recognition result; a program management table for managing program management data indicating a speech recognition interface function required by each application program; and a message processing unit for exchanging messages with the plurality of application programs in order to specify an appropriate recognition vocabulary to be used in the speech recognition processing of the speech input to the speech recognition unit, and to transmit the recognition result for the speech input obtained by the speech recognition unit by using the appropriate recognition vocabulary to appropriate ones of the plurality of application programs, according to the program management data managed by the program management table.