To provide a video doorphone unit that employs digital data for a video signal and an audio signal similarly to the case with control data.

The video doorphone unit wherein a camera attached entrance slave unit 1 is connected to a monitor attached master unit 3 via a transmission line L1, and a speech is made between a slave unit microphone 16 and a slave unit speaker 17 of the camera attached entrance slave unit and a speech unit 37 of the monitor attached master unit in response to a call from the camera attached entrance slave unit while a video image imaged by a camera is displayed on a monitor of the monitor attached master unit and visually confirmed, includes a slave unit data communication circuit 20 and a master unit data communication circuit 31 which transmit/receive a digital video signal imaged by the camera, a digital voice signal resulting from digitally converting a signal received by/outputted from a microphone, a speaker and the speech unit and a digital control data signal required for controlling calling, a video image and a speech on a transmission line.