In a signal receiving circuit there are provided N input detection circuits 2a to 2n for receiving clock signals S1-c to SN-c included in N channels of signals S1 to SN. Each of the input detection circuits 2a to 2n detects the transition of the input signal of the corresponding channel and further confirms that the signal of the corresponding channel is being received after the transition detection to thereby detect the input of the signal of the corresponding channel. The selection circuit 3 selects and outputs the clock signal and the data signal in the signal of the channel of which the input is detected. The selected output signal is successively subjected to input processes through one each of the phase synchronization circuit 4, the serial/parallel conversion circuit 5, etc., which are shared by N channels.