Abstract: The gas flow path in coal body is mainly composed of slits and pores, which is a typical dual gas flow path structure. Generally, in order to quantify the apparent permeability of gas transport in different scale flow paths, mathematical models of permeability are established using the pore or slit structure of single flow path. With the development of microstructure characterization technology, the characterization of slits and pores in real coal is more accurate, and the permeability model based on single flow path is obviously not accurate enough. Therefore, in this paper, the micron scale gas flow path is simplified into two geometric forms of slit and pore. High-precision CT technology is used to obtain the volume proportion of pore and slit structure in the total gas flow path, namely pore porosity and slit porosity. Then, the parameters are substituted into the statistical distribution model of permeability, and the overall apparent permeability with slits and pores is obtained. Finally, the calculation results of apparent permeability of single flow path pores-based model, slits-based model and the dual flow path pore-slit-based model are compared and analyzed. The results show that the slit-based apparent permeability model overestimates the actual apparent permeability, but the pore-based apparent permeability model underestimates it, and the mixed pore-slit-based permeability is in between. From the mean value of relative deviation of apparent permeability calculated for single gas path structure and dual gas path structure, the mean value of relative deviation of pore-based apparent permeability is no more than 50 %, which is closer to that of the real dual flow path pore-slit-based apparent permeability.