Abstract: To effectively study the characteristics of pore structure of coal with different coal structure, based on the concept of refinement, nondestructive, and quantitative, with the high resolution Micro-CT System μ CT225kVFCB, the characteristics of pore distribution for 4 coal samples (undeformed coal, cataclastic coal, foliated coal and mylonitic coal) were obtained on a macroscopic scale. Using microscopic CT slices, combined with the scan electron microscope (SEM) images, the pore types and structure characteristics of different coal microstructures were observed directly and the influence of tectonic deformation on pore structure was researched. The results show that the pore diameter of coal with different coal structure is commonly less than 5 μm, but the later stress changes pore structure. Compared with the normal coal, the cataclastic coal has well-developed exogenetic pore and micro-fracture due to brittle failure, which results in the biggest surface porosity and mean pore diameter. In the mylonitic coal stage, mylonite occurs due to the plastic deformation, which fills in some pore-fractures and results in the reduction of surface porosity and mean pore diameter.