Aiming at the problems of large data transmission and high dependence of the primary station in the single-phase ground fault location of distribution network, a small current ground fault location method based on edge-end coordination is proposed. On the basis of constructing the fault location architecture based on D-IoT, the basic principle of "edge-end" collaborative task hierarchical deployment and edge-side autonomous decision-making is given. According to the opposite characteristics of the transient zero-sequence current mutation direction in the upstream and downstream of the fault point, the SOD transform is used to calculate the eigenvalue of the catastrophe and uploaded to the edge terminal. The “edge” side constructs the fault information matrix by locating the service-related application interaction. Realize the combination of topology information and fault information, finally, the fault unified decision is applied to complete the fault section decision. ATP simulation and field experimental data verify the correctness and effectiveness of the algorithm.