Abstract: The paper introduced a new type of intelligent low-voltage feed switches used in distribution system of coal mine underground and expounded design of hardware and software.The feed switch took PLC as core and set up overload protection,short-circuit protection,leakage protection,over-voltage and low-voltage protection.Meanwhile,it had functions of man-machine conversation and communication.The field test showed that the feed switch had high precision and could improve the security and reliability of power supply system of coal mine greatly.