Based on the theory of the zero-sequence current phase's fault location method, this article proposes a location algorithm by comparing the relationship between the time and phase radian. The implementation of this method is to use GPS(Global Positioning System) second pulse for synchronous sampling by extracting zero-sequence current, then transmit the collected phase information by the wireless communication module, and confirm the fault interval by the central station software ultimately. Considering the distribution network's branch line may result in wrong fault location, we put forward the corresponding solution. Finally, I make the analogue simulation aimed at variety of situations of distribution network's single-phase ground fault by using the simulation module of MATLAB. And I verify the fault location method is feasible by observing phase waveforms of the zero-sequence current in every outgoing line.