Abstract: Taking the 1007 fully mechanized caving face in Xiakuotan coal mine as the research background, FLUENT software is used to simulate the gas migration law in goaf under sandstone roof condition.With the advancement of the working face, the overlying roof rock falls into the goaf, and the rock mass with high mass collides with each other during the slumping process.On the one hand, high temperature friction points are generated in the goaf with frictional sparks.On the other hand, it has a great influence on the permeability of the porous medium in the goaf, and a large number of rock blocks fall together, which provides favorable conditions for the free escape and mixing of gas in the goaf.Through simulation analysis and research, it is possible to avoid the occurrence of gas explosion accidents as much as possible, and provide a reliable basis for coal mine safety production.