Abstract: In order to explore the law of smoke spread of belt fire in the intake airway of the fully mechanized mining face with large mining height. The smoke spread, temperature, CO concentration and visibility in the roadway are simulated by FDS. The results show that the smoke can spread to the fully mechanized mining face within 60 s, and can be completely filled in the fully mechanized mining face at 420 s. When the fire occurs 90 s, a dangerous area of high temperature and high CO concentration will be formed at the end of the downwind side of the intake airway, and the temperature and CO concentration can reach 150 ℃ and 175 ppm or more; when the smoke continues to flow in the fully mechanized mining face, a plume-like high concentration area of CO will appear in the range of 50 m to 150 m, and the local concentration can reach 147.73 ppm, which is significantly higher than other areas.