Abstract: In view of problems of higher power consumption and difficult design of intrinsic safety of WiFi terminals used in coal mine underground, a mine-used location-based services terminal based on WiFi was designed. Hardware structure and design principle of intrinsic safety of the terminal were given, software design of the terminal was introduced in details, including design of WiFi driving program, implementation of a new underground personnel location mechanism which meets with special environment of roadway and implementation of location-based services of wireless voice communication, real-time monitoring of gas concentration and image data collection under SIP protocol. The experiment result shows that personnel location precision of the terminal is in 1 m, transmission of voice communication and image data has no delay and the longest time of gas concentration collection under low power consumption mode is 7 h, which meets with requirements of mine production and intrinsic safety.