In order to ensure the safe and stable operation of high voltage power grid of coal mine,the prevention of power grid management is primary,which attaches great importance to the overall safety evaluation and analysis of power system.This study tested and analysed the corresponding parameters of coal mine power supply system,and then conducted the simulation modeling,made comprehensive evaluation and thematic analysis of the power supply system of coal mine power supply quality and reliability,and mainly for testing of high voltage power supply system of single phase grounding electric current,neutral point grounding and grounding protection evaluation and analysis,and finding out the the problems of the system and the safety hazard on the basis of the analysis,providing the suggestions and solutions for further renovation or expansion,while ensuring the safety in the production of coal mine.