Abstract: The mine distribution network is located at the end of power network and is one-terminal power network.Aiming at the attributes above,a new real-time and on-line method using wireless sensor networks is presented in this paper.Signals are transferred to sink nodes by multi-hop routing protocols and the fault points can be judged through the direction of traveling wave and the position of nodes.Based on this method,a fault location system,which is composed of wireless sensor nodes,wireless gateway and fault manage system,is designed and the consistency principle of corners and joints is put forward.Some measurement methods using directional antenna and special adding nodes in the corners etc are proposed to improve the transmission efficiency of radio in the coal mine tunnels and a mesh-lineal mixture topology is also presented at the end of this paper.