PURPOSE: To eliminate complicated operation of the connection/interruption of a telephone line at every call by permitting a callee telephone set to transmit a facsimile data signal in response to a pseudo signal which can be received.

CONSTITUTION: When a caller-side is in a facsimile equipment and it requests facsimile communication, a telephone set 1 spuriously transmits a standby signal showing that the facsimile data signal can be received. Since the facsimile equipment receiving the standby signal transmits the facsimile data signal, the telephone set 1 is prevented from repeatedly being called by a dial function with which the facsimile equipment is provided. Thus, the troublesome operation that an operator connects/interrupts the telephone line at every call of the telephone set 1 can be eliminated. The pseudo signal is transmitted when an identification signal showing that the caller-side is the facsimile equipment is detected. Thus, the caller-side is prevented from being operated and called by a redialing function.