Abstract: The gases produced by coal spontaneous combustion(such as CO,H₂,C_nH_m,CH₄) can explode in open-light mine.High-gas flammable coal mine is an important component of gas,which increases total concentration of gas,expands boundaries of gas explosion reduces the oxygen demand of explosion.Strong fire source of burning can led to the gas explosion in low concentrations and hypoxic condition.Anti-gas accidents should be anti-coal spontaneous combustion first in such mines.