The increasing diversity of access elements and complexity of network structure bring new difficulties to the fault location in distribution network. With the help of regional integration of electrical information, a fault location method based on fault-network state estimation for distribution networks is proposed. Firstly, the fault network description model is established, and the fault event is described as the change of network topology and expressed by Kirchhoff equations. Then, to uniformly represents the fault conditions of different components through fault network, a standardized fault network description to represent different possible fault occurrence at a fault component is pointed out. Furthermore, the distribution network state estimation is carried out with the help of different fault networks representing different component faults, and the matching degree of the state estimation results of different fault networks is calculated The distribution network fault location function is finally obtained through the matching degree comparison of the state estimation results. Finally, the effectiveness of the proposed method is verified by case simulation under different fault types and transition resistors, and the fault location performance is further tested in the case of abnormal data. The results show that the proposed method also has a good ability to resist bad data.