Abstract: Oxidation high temperature of floating coal in goaf leads to CO concentration overrun and spontaneous combustion of residual coal during coal mining at 5244 fully mechanized caving face. In order to ensure coal mining smoothly, fire preventing and extinguishing technique for working face is studied. Through the technical measures such as grouting, nitrogen injection, gel injection and the application of new type fire preventing and extinguishing material named Shidafu fire extinguishing agent, good results are achieved. Through the analysis of gas sampling, it is found that CO concentration remains at around 12×10^-6, which effectively prevents the spontaneous combustion of residual coal and ensures coal mining smoothly and safely.