PURPOSE: To receive surely a communication control signal at a receiving side, by transmitting the same control signal in several times in transmitting a control signal in the facsimile communication system using a line of the same directivity.

CONSTITUTION: In transmitting a facsimile signal on a radio line of a single frequency, after control signals 1a, 1b of the signal form are transmitted, and the next end procedure control signals 3a, 3b are transmitted with the same form. The receiving side receives surely the control signal not received once because of noise or monentary interruption of line by detecting either one of the control signals 1a, 1b or the signals 3a, 3b, to discriminate accurately the operation.