Abstract: There are many problems with on-line monitoring, and the warning capacity is weak in roadway roof, an on-line monitoring and warning system of roof abscission layer based on industry web is proposed. By building a wireless sensor network based on ZigBee protocol, the hardware and software design are introduced in paper, and the overall design. implementation of down hole environmental data collection, transmission, and then via the industrial Ethernet will collect data sent to the monitoring center computer. According to the requirements of system data fusion, is proposed in this paper, based on fuzzy closeness and two levels of data fusion model of grey correlation degree. The test results show that the system is able to on-line measure accurately for roof abscission layer in gob-side entry driving of mine, the error could be kept on ±4.8, and the early warning capacity is improved effectively.