In the safety production of coal mine, monitoring exact and real-time mine parameter is very important and key problem. The monitoring system of mine environment with wireless is designed, which is based on the structure of wireless sensor network (WSN).The system includes sensor node, Sink node and monitoring center. In the paper, the function structure and hardware design of sensor are introduced for the monitoring of temperature, humidity and gas concentration, and the function structure and hardware design of sink node is designed. The system has low power, rapid real-timing, stable running. Etc. This can satisfy with the requirement of WSN and suit the monitoring of bad environments. It will have wide application prospect.