Distribution network automation is a combination of modern communication, computer, automation and network technology, real-time monitoring of distribution network equipment from afar, and advanced grid management technology to optimize grid operation. Using this technology can quickly and accurately identify the fault of the distribution network, and isolate and restore the power supply in time, which can greatly reduce the time of the line failure of the distribution network and enhance the reliability of the power system operation. This is also the future development of the power system. Aiming at the problem that the previous distribution network fault location methods based on the fault indicator system cannot effectively identify single-phase grounding faults, this paper adopts a digital fault indicator distribution network intelligent fault location system, which mainly applies the signal injection method The fault indicator system can reflect various types of power distribution network faults, and the application cases are cited for a comprehensive analysis.