To prevent the futile operation of a communication terminal and the wasteful charge to an opposite party by detecting whether or not a reception operation as a facsimile equipment is possible when the opposite party is judged to be the facsimile equipment, separating the communication terminal from a line when impossibility is detected and transmitting a line disconnecting signal.

A control part 101 monitors a DCDET signal in a stand-by state. When a telephone set 16 responds to a call signal from the line, a D.C. current is permitted to flow in a current sensor and the DCDET signal is outputted form a comparator. When it is detected, the control part 101 detects a CNG signal. Since the CNG signal is transmitted when the opposite party is the facsimile, the CNG signal is detected and it is judged whether the facsimile operation is executed or not. When reception impossibility such as the run-out recording paper sheets in a recording section 102 is judged, the telephone set 16 is separated from the line, the line is connected to the facsimile, the line is changed-over again, the line is disconnected and, then, return to stand-by is executed.