Latch-up of each of parasitic thyristors (T1-T4), which occurs when a circuit element (B1) is formed on a semiconductor substrate in which an IGBT (Z1) has been formed, is prevented by a circuit for preventing the latch-up using Schottky barrier diodes (D2, D3) formed on the semiconductor substrate. Each of the Schottky barrier diodes (D2, D3), which is composed of a junction between a diffused layer used for forming the circuit element and a metal wiring layer, is used in the circuit for preventing the latch-up action of each of the parasitic thyristors (T1-T4). Thereby, the area of the semiconductor device can be made smaller while the semiconductor device can have a higher protection effect.