The invention provides a power semiconductor device for an igniter, which achieves overvoltage protection of a power supply with a simple structure that does not prevent the miniaturization or simplification of a whole device and has a high reliability. The primary current of an igniting coil (6) is electrified. A cut first semiconductor switch element (4) is connected to the igniting coil (6) in a parallel connection, thereby a second semiconductor switch element (35) embarked on an integrated circuit (3) is electrified and a third semiconductor switch element (300) is conducted. In this case, the overvoltage of the power supply is monitored and the first semiconductor switch element (4) can be protected from overvoltage.