Abstract: The small current grounding power system is simulated based on the dynamic simulation tool Simulink and simpower system toolbox. The model’s creation has been discussed. The zero sequence voltage and zero sequence current waveform characteristics are mainly analyzed for single phase to earth fault. The short circuit current waveform characteristics are analyzed for two phase short circuit, three-phase short circuit. The characteristics of zero sequence current, zero sequence voltage and fault phase voltage are analyzed. Through the simulation of the main fault waveform of the system, the main waveform characteristics of each fault, the difference of the characteristics of different fault waveform can be fully understood, which is conducive to the subsequent fault detection and identification.It provides a basis for fault analysis and research of small current grounding system, and it has important significance for the research of fault detection algorithm and equipment in small current grounding system.