Abstract: Coal bed gas migration is a basic scientific problem in the field of mine gas drainage and coal bed gas development in coal mine areas. This paper expounds the research status of the theory of coal seam gas migration and the testing method of its permeability characteristics in China from two aspects of theoretical analysis and test methods, and focuses on the latest achievements and understanding of the key issues such as the nonlinear seepage characteristics of coal seam gas and the seepage theory under multi-field coupling. Further analysis is made on the test methods of coal seam gas transport characteristics commonly used at present, and research suggestions are as follows: in-depth research on the reproduction of the real stress-strain state of coal body around the borehole, the evolution characteristics of coal porosity in the gas permeation process, and deepening the understanding of the nonlinear seepage model of coal seam gas, and the evolution of gas transport characteristics in accordance with the permeability improvement or stimulation measures. Based on the adaptive multi-field and multi-factor coupling model established.