Abstract: The single-phase grounding fault characteristics of the distribution network system via low resistance grounding mode will be affected by the grounding mode adopted by different types of grid-connected DGs. Aiming at the problem, combined with the symmetrical component method, a single-phase grounding fault analysis model of distribution network with multiple grid-connected DGs having different types and grounding modes is established first. The single-phase grounding fault point current of the system and the three-sequence current of the line are analyzed afterwards. Finally, the simulation model of single-phase ground fault is built by Matlab/Simulink, which verifies the correctness of the analysis of fault current characteristics. The results show that the grid-connected DG being ungrounded has the least impact on the system fault characteristics. This provides a theoretical basis for the selection of the type of grid-connected DG and the grounding mode of the grid-connected transformer.