PURPOSE: To attain intercom talking by the interphone main device with conve nience of use.

CONSTITUTION: The interphone main device A is provided, to which an intercom D and a telephone set C are respectively connected. A channel is formed between an external line L1 and the telephone set C in the interphone main device A to make external line talking. Furthermore, a channel is formed between the intercom D and the telephone set C to make intercom talking. A hand-free talking section is integrated with the interphone main device A. The hand-free talking section consists of a microphone 10, a speaker 11, a voice switch circuit 14 and amplifier circuits 12, 13. A channel is formed between the hand-free talking section and the intercom D by a talking control means at a reply of the hand-free talking section for an intercom talking to make the intercom talking. Doorphone talking is executed without having a receiver or a handset in the interphone main device A to improve the convenience of use.