Abstract: The temperature and gas composition in goaf were determined and analyzed by installed temperature sensor and sampling strap tube along the strike in goaf of No.3410 fully mechanized working face of Qinan Coal Mine. According to the standard of oxygen concentration divided spontaneous combustion "three zones" range, the range of spontaneous combustion "three zones" in goaf of the 3410 fully mechanized face was determined and the minimum advancing speed was 63.75m/month in terms of spontaneous combustion "three zones" width.