Abstract: To investigate the methane adsorption characteristics of different soft and hard coals, Dongqu Coal Mine in Gujiao Mining Area, Shanxi Province, was selected as the research object. Aimed at two groups of soft and hard coal samples with different coalification degrees, the high pressure capacity method was adopted to measure the methane adsorption properties of these samples. Low temperature liquid nitrogen adsorption experiments were carried out for these soft and hard coal samples and their pore structural characteristics were also analyzed. On the micro structure level, the control mechanism of methane adsorption was revealed for these soft and hard coal samples. The research result shows that gas adsorption capacity differs greatly among soft and hard coals. The greatest value of Langmuir volume V_L is 1.5 times of the lowest value. Among all the samples, the proportion of micropores is more than 50%, and the pore specific surface area in coal is mainly contributed by micropores (< 10 nm). The original pore/fracture systems in coal seam are destroyed by tectonic deformation, leading to the reduction of pore diameter. As a consequence, the proportion occupied by micropores increases, and the pore specific surface area is also increased. Thus, the adsorption capacity of soft coal is significantly higher than that of the corresponding hard coal.