Abstract: Based on μCT technology, three-dimensional CAD model and three-dimensional model are adopted to realize the three-dimensional modeling of coal pore cracks in different coal structures. We quantitatively characterized the pore fracture morphology, size and space configuration of primary structural coal and structural coal at different scales, and evaluated the permeability of coal. The results show that the spatial development orientation and mineral filling degree of pore fissures of primary structural coal determine the anisotropy of permeability; in comparison of primary structural coal, the fracture width and density of broken coal increased, the porosity and specific surface area increased, and the probability of permeability was the highest, and the fractures in different directions in the micro area were connected into the pore fissure network with different levels and configurations to improve the gas seepage capacity; mylonitic coal forms an isolated pore fissure structure with high spatial heterogeneity and lowest percolation probability. Compared with the traditional method, the study concludes that although the accuracy of spatial resolution (1 μm) is limited, the μCT technology has the advantage of nondestructive detection of structural characteristics of three-dimensional hole cracks in structural coal.