Abstract: The measurement and calculation methods of coal seam permeability proposed by scholars at home and abroad were studied, the calculation model of gas migration in coal seam was analyzed, on the basis of these, some assumptions of coal seam gas seepage were proposed. The calculation equation of radial flow of coal seam gas was established by using the momentum conservation equation and gas state equation, and the permeability calculation equation was established according to the boundary conditions of the actual situation in the field, in order to provide theoretical support for field penetration test. Based on the research of laboratory and field test methods, a new method to measure the permeability of coal seam was presented, named circumferential permeability test. The coal seam permeability of 27 mining area in Macun Coal Mine was measured by using this method, and compared the calculated permeability coefficient with former measured data, the results showed that the method can directly measure the permeability of coal seam, and the test results were accurate and reliable.