Abstract: In order to grasp the actual situation of spontaneous combustion in 35002 fully mechanized caving face of Liangbaosi No. 2 Mine, by means of the measurement of O₂ concentration and temperature with the advancing distance change of working face, spontaneous combustion “three zone” distribution of 35002 fully mechanized caving face is studied. We determine the range of spontaneous combustion “three zones”, 0 to 34 m as the heat dissipation zone, 34 to 92 m as the oxidization and heat accumulation zone, 92 to 118 m as the asphyxia zone, in the goaf of the fully mechanized working face. Through calculation, the safe advancing speed of spontaneous combustion in the goaf of 35002 fully mechanized working face is 74.5 m/month, and the measures to prevent coal spontaneous combustion in goaf in different mining periods are proposed.