Coal properties are one of the three main important affecting factors on coal adsorption capacity. In this paper, coal samples from Northern and Northwestern China, where coalbed methane resources are very rich, were analyzed in petrolog y, chemistry and isotherm adsorption. Then the influence of coal rank, maceral and coal deformation on coal adsorption capacity were discussed. The results indicate that the relationship between coal adsorption capacity and coal rank appeared a reversed U-shaped trend in the condition of water equilibrium. Coal adsorption capacity changed abruptly during coalification corresponding to four coalification jumps, which was controlled by CH4 affinity and porosity changes of coal during coalification. The adsorption capacity effect of inertinite was clear when its concentration was high, which was mainly related to high adsorption capacity of fusinite in inertinite. Surface physicochemical changes caused by tectonic stress was a main reason for deformed coal to possess the strongest adsorption capacity than other normal coal from the same mine and the same coal seam.