Abstract: In order to study the actual fire-fighting effect of injecting liquid carbon dioxide into the oxidation zone of the goaf area on the 010905 working surface of Wuhushan Coal Mine, surface drilling was designed in the right position of the goaf area at the back of the working face, and liquid carbon dioxide was directly injected into the surface of the oxidized zone of the working face. After a large amount of liquid carbon dioxide was vaporized, the temperature, oxygen concentration and harmful gases were effectively controlled, ensuring the safe mining of the working face. After the liquid carbon dioxide is directly injected into the surface of the borehole, the prearranged beam tube and sensor are used to observe. The results showed that: the temperature and oxygen concentration in the test area showed a linear decline trend, while the CO₂ gas concentration showed a sharp rise first and then a continuous decline trend, and the treatment effect was obvious.