A CI signal of a V.8 protocol is transmitted in response to the reception of a DIS signal indicating the provision of a V.8 facility, and the V.8 protocol is executed in response to the reception of an ANSam signal of V.8, and when the DIS signal indicating the provision of the V.8 facility is received without receiving the ANSam signal, the CI signal is retransmitted. When a transmitting station or a receiving station does not have a V.34 facility after the V.8 protocol, the DIS signal indicating the non-provision of the V.8 facility is transmitted. Thus, when the V.8 protocol facility is provided with a facsimile apparatus, communication with a conventional apparatus having only a T.30 protocol is attained.