Abstract: Only one fault section can be diagnosed by the amplitude\|comparison or phase\|comparison method, so a fault section location algorithm which is suitable for locating multiple single\|phase grounding faults in isolated neutral system is proposed in this paper. Through analyzing the phenomenon of multiple single\|phase grounding faults occurring in isolated neutral system, the network describing matrix is built by using of the amplitude\|comparison method. Then it is modified according to specified algorithm, and the fault judgment matrix is obtained, by which the fault section can be determined. In addition, the fault section that may be mal\|judged is eliminated by phase\|comparison method, and possible fault sections located between first two feeder terminal units (FTU) on fault paths and on each line at power source side are determined. In the end, MATLAB simulation results verify the correctness and feasibility of this algorithm.