A sign language interpretation system has a function to interconnect a deaf-mute person terminal, a non-deaf-mute person terminal, and a sign language interpreter terminal, and a function to synthesize a video/audio signal received from each terminal and to transmit a synthesized signal to each terminal in order to provide a videophone conversation service via sign language interpretation between the deaf-mute person and the non-deaf-mute person. A controller includes a sign language interpreter registration table in which the selection information and terminal number of a sign language interpreter as well as an availability flag are registered. An available sign language interpreter satisfying the selection conditions specified by a caller is selected by way of a call from the deaf-mute person or non-deaf-mute person. The terminal for sign language interpreters and the calling terminal are called and automatically interconnected.