Abstract: The production horizons in Hancheng area of Shaanxi province are characterized by longitudinally alternating coal lithotype changes and strong heterogeneity in the coal seams. The relationship between the coal lithotype and the microfissure development are analyzed by means of microscopic observation and fractal approach, combined with X-ray CT and NMR T2 spectrum analysis technologies.The results show that the microfissures are dominated by the dendritic and orthogonal types with length of over 300μm and width of less than 5 μm, and much more developed in bright coal and semibright coal. The NMR T2 spectrum analysis indicates that from bright and semibright coal to semidull and dull coal, the trimodal pore-size distribution of adsorption pore, seepage pore and fissure is changed to bimodal distribution of adsorption pore and seepage pore. The development degree of microfissure and the connectivity between adsorption pore and seepage pore are gradually weaken, with the trend of the adsorption pore increase, showing a good consistency between the NMR T2 and the X-ray CT results. It is suggested from the microfissure development characteristics of different lithotypes and the correlations to coal macerals that hydrocarbon generation potential and its diffusion ability are the key factors of the microfissure development