Abstract: In order to control the high temperature fire zone and CO abnormal emission in the underground mine of Xinshun, based on the comprehensive analysis on the fire cause, the radon measurement and fire detection technology with isotope was applied to investigate the fire location, scope and development tendency.Mean while, the fire monitoring, measuring, control and the grouting for sealing was enhanced .According to the actual conditions of the fire zone, the borehole drilling and gel injection technology for the fire extinguishing and temperature control was conducted in the underground mine.The application results showed that based on the detail fi re location detected, the borehole drilling and gel injection for the fire extinguishing was conducted to fully play the gel function to seal the leakage, to absorb the heat a nd to control the temperature.The applied technology would be easy in construction technique and the material applied would have wide resources.The applied technolo gy would have obvious fire extinguishing effects and the temperature in the applied zone could be reduced by 66%.