Abstract: Based on the practice of the determination of the gas parameters in Jingfu Mine, applying the methods of numerical simulation and theory analysis, combined with the stress distribution laws and gas migration laws in the seam, analyzing methane migration laws in the drilling, the results show that the seam near the drilling could be divided into three zones, pressure relieved and permeability enhanced zone (0.095 meters far from the drilling center), pressure increased and permeability declined zone (0.139 meters far from the drilling center), initial rock stress zone; the permeability declined zone would prevent the gas from leaking out at first, with time going on shrinkage deformation occurred in the coal, the permeability coefficient raised even in and beyond the permeability declined zone. Jingfu Mine could extract gas well through the borehole as calculation proved.