Abstract: As to the single phase grounding fault in 10kV power distributed lines, a fault locating system for distributed network is proposed based on AC/DC comprehensive detecting method and GPRS communication to realize automatic locating for fault region of power distribution network. The features and application area of DC and AC detection are analyzed. In addition, the remote data transmitting by using of GPRS communication technique is presented to avoid people climbing up to wire pole, and to improve the speed of DC detection, which can lessen the difficulty of AC detection. In this system, the hardware of communication system is designed with low power loss, and power saving mode is applied in software design to make data transferring more reliable. AC/DC comprehensive detecting method is used in this paper to effectively deal with all kind of single-phase faults with grounding resistance less than 20kΩ, which will shorten fault detecting time and improve reliability of power supply.