Fault location technology can greatly improve the speed of fault line inspection and repair, but the existing small current grounding fault location technology in a distribution network has the problem of poor economy. Therefore, a small current grounding fault location method based on the distribution characteristics of zero sequence voltage and can be realized on the existing distribution network automation system is proposed. First, the distribution parameter equivalent circuit of a small current grounding fault is used to verify the feasibility of zero sequence voltage distribution as a fault location criterion. Secondly, based on the known fault section, the distribution automation system is used to obtain the fault zero sequence voltage information of limited detection points, and the zero sequence voltage distribution function of upstream and downstream sections of the fault point is obtained by function fitting. Finally, the simultaneous equations of the zero sequence voltage distribution function of the two sections are solved to obtain the location of the fault point. The test results of simulation and field data show that this method has high ranging accuracy, can be realized by existing equipment, and has good economy. This work is supported by the National Natural Science Foundation of China (No. 52077221).