A new scheme for distribution lines fault location based on the wireless sensor network is presented and requirements on the fault location system are made according to the need of power system fault location and the features of the wireless sensor network. The advantages of using the wireless sensor network in the fault location are described and the fault location principle is derived. The structure of the positioning system based on the wireless sensor network is designed and the synchronism problem is solved by means of a synchronization device. The reliability of this network is satisfied using the multi-path reliable information routing mechanism. Simulation results show that this mechanism can not only meet the reliability requirement but also reduce the network cost.