Abstract: The paper introduces a kind of design scheme for soft start circuit of intrinsic safety type anti-interference power supply used in coal mine electrical equipment. This circuit has the characteristics such as electromagnetic compatibility, ia class safety and current slow shock; in particular, it has obvious inhibitory effect on wave surge, pulse swarm, static interference; at the same time, the power on electric current slow start is good, and the intrinsic safety is high; the designed anti-interference power supply soft start circuit is suitable for widespread use in coal mine.