A handsfree video phone system includes a video phone terminal and a car device in which a microphone, a speaker, and a camera are connected with an instrument panel via a cable. The video phone terminal is connected with the instrument panel via a wireless communication medium. When the video phone terminal is brought into the vehicle, the instrument panel informs the video phone terminal of the attribute information on the system structure. According to the attribute information, the video phone terminal switches the paths of multiplexed audio-video data so as to replace a microphone, a speaker, a camera, and a display that have been built in the video phone terminal with the microphone, the speaker, the camera, and a display of the instrument panel when the status changes to the communication status.