In this paper, a monitoring and controlling system for the safety in production and environmental parameters of a small and medium-sized coal mine has been developed after analyzing the current domestic coal production and security conditions. The client computer can convert the analog signal about the safety in production and environmental parameters detected from the monitoring terminal into digital signal, and then, send the signal to the coal mine safety monitoring centre. This information can be analyzed, judged, and diagnosed by the monitoring-management-controlling software for helping the manager and technical workers to control the actual underground production and security situations. The system has many advantages including high reliability, better performance of real-time monitoring, faster data communicating and good practicability, and it can effectively prevent the occurrence of safety incidents in coal mines.