Abstract: Through the research of stress metamorphism character of coal seam Ⅱ1 in Ludian gliding structure,the stress effecting factors of metamorphism and hydrocarbon generation process of tectonic coal are studied.As a result,it is showed that different tectonic stress have different effect on coal evolution.Compared with the tensional stress,compressive stress which has appareant anisotropic characteristics produces more accelerating process for abscission of side chains and functional group of basic structural unit(BSU),increase of coal metamorphic degree and generation of coal seam gas.