Abstract: In order to prevent coal spontaneous combustion effectively, the change laws of the gas composition were determined in the goaf of 11102 fully-mechanized caving face of Hetuo Coal Mine. Combined with the spontaneous combustion theory of the coal in the goaf, the distribution range of three zones of spontaneous combustion was determined. On this basis, the Fluent software was used to analyze the reason of abnormal distribution for the inlet and return air side in spontaneous combustion zones. The results showed that the inlet and return air corner closure in fully-mechanized caving face of Hetuo Coal Mine and the embedded pipeline gas pumping in goaf were the main reasons for this condition.