This paper described a monitoring and warning system for brae debris flow, which based on Zigbee protocol while the GPRS and Internet to accomplish remote data transmission. This distributed system comprises sensor nodes, coordinator nodes, data transmission module and terminal management module. In this paper, the design and architecture process of the hardware as well as software are also introduced in details. In order to make the system easy to manage and maintain, modular design methods are chosen. This system can monitor in real-time and save human resources, which are unsolved in traditional ways. So, it is very suitable for monitoring and warning brae debris flow or other geologic hazard.