Abstract: At present, there are many simulation studies on gas explosion in underground roadways, but most of them lack the basis of reference to the specific parameters of underground roadways.In order to analyze the evolution characteristics of the flow field of gas explosion shock wave accurately, the Majin’ao coal mine in Liling city, Hunan province is taken as the research object, and numerical simulation software is used for the temperature field, stress field and shock wave propagation law when a gas explosion occurred in the mine tunnel.And the change law of the velocity field are analyzed in more detail, combining with theoretical research, the simulation results are fully explained; the temperature and overpressure load generated in the explosion process change with time, the general law formulas of temperature and overpressure load are obtained; focusing on the gas shock wave velocity difference between the open end and the closed end of the tunnel in a gas explosion, analyzing the propagation process and wave form of high-speed flowing gas, and find that the unstable state of gas and pressure is important influencing factors.The research results show that through simulation research with reference to actual geological data, it is concluded that the sharply rising temperature and overpressure are the main factors that damage the downhole safety facilities, which provides an important research basis for the prevention and control of underground gas explosion.