Abstract: To analyze the laws of gas explosion accidents in our country coal mines, the paper selected the gas explosion accidents during 1950-2000 as samples, analyzed the time and space distribution, the first class hazard and the second class hazard traits of gas explosion accidents on the whole and different gas grades. It showed that gas explosion accidents not only had concentricity on the space-time and hazard characteristics, but also had different grades for different gas coal mines, and it explained the dissimilarity.