Abstract: In order to study the change of pressure, temperature and other parameters during gas explosion, using Simtec software and based on the large eddy model simulation, the premixed gas explosion process was studied when the volume fraction of methane in the closed near-sphere container was from 6% to 14% under the condition that the wall radiation coefficient was 0.9 and 0.1 respectively, the simulation results were compared with the published experimental results. The results show that the simulation results are in good agreement with the experimental results when the wall radiation coefficient is 0.1; the explosion pressure and temperature first increases rapidly and then decreases, the temperature decreases slowly and fluctuatedly; there is a positive correlation between the maximum explosive overpressure and the maximum pressure rising rate on the left side of the peak and a negative correlation on the right side of the peak.