Abstract: In view of request of on-line environment monitoring of coal mine underground,the paper proposed a design method of underground wireless sensor network node for real-time monitoring,introduced hardware composition and software design of the wireless sensor network node.The node can collect,process and transmit data of gas concentration,CO concentration,temperature and humidity of underground working face by microcontroller and wireless transmission module.The test result showed that the node is convenient to control and runs stably,which can realize reliable wireless network transmission.