Abstract: The selection and location of single-phase-to-ground faults remain a challenging problem in power systems. This paper, through model abstraction and fault feature analysis, finds that after a single-phase-to-ground fault occurs in a distribution network, the grounding resistance of the faulted phase causes distortion in the three-phase parameters of the distribution network. After a single-phase-to-ground fault, the distortion is greatest in the faulted feeder and the upstream feeders of the faulted phase. Therefore, the asymmetry of the three-phase parameters in the distribution network can be used to locate single-phase-to-ground faults, and based on this, a method for locating such faults using three-phase parameter asymmetry is proposed. Experimental results show that the proposed method is simple to implement and exhibits strong robustness to different fault locations and grounding