Abstract: A phone conference system for making a conference using a plurality of phones which comprises a voice response board 6 for receiving push tone signals and voice signals transmitted from each phone, for transmitting push tone signals and voice signals, and for recording and reproducing voices in response to push tone signals, a voice synthesis board 8 having a plurality of conference rooms 16 in which voice signals from each phone received at said voice response board 6 are synthesized, and a control section 18 for controlling status of voice synthesis board 8 and for receiving line information from each phone and transmitting orders concerning connection by exchange of lines to voice response board 6 in response to status thereof. The control section 18 designates a conference room 16 to be connected to each line in regard to a plurality of lines received at voice response board 6. The voice signals of plurality of lines are synthesized and are connected by exchange in designated room.