PURPOSE: To prevent the breakdown of a driver element or the like on the load side by easily setting the timing of a control signal on the control side.

CONSTITUTION: This optical coupling semiconductor device is provided with light emitting diodes 10 and 20, a light reception part, and output control circuits 13 and 23. The light reception part is provided with photo diodes 11a and 21a for input signal transmission which receive the light from light emitting diodes 10 and 20 to transmit a signal and photo diodes 11b and 21b for control signal transmission which receive the light from light emitting diodes 10 and 20 to transmit it as a control signal to another channel. The signal from photo diodes 11a and 21a for input signal transmission and the control signal from another channel are inputted to output control circuits 13 and 23, and these circuits output the signals from photo diodes 11a and 21a for input signal transmission by the control signal.