In view of problems of low measurement accuracy, delayed data transmission and inconvenient equipment deployment existed in current coal seam gas pressure monitoring, a coal seam gas pressure monitoring system based on 6LoWPAN was designed. In the system, pressure measurement node selects the optimal path in 6LoWPAN network through multi-hop mode, so as to transmit gas pressure data collected in real time to border router. The border router transmits the data to ground server through industrial Ethernet, and ground equipment can query real-time monitoring data of pressure measurement node in specified area through the server. The test results show that the system can real-timely and accurately monitor coal seam gas pressure with high data communication efficiency and stability and low power consumption.