Abstract: In order to investigate the controlling of the sedimentation environment evolution on the coalbed methane system in Xishanyao Formation on the southern margin of Junggar Basin, using drilling wells, logging wells, outcrops and other data with the assistance of fine analysis methods, such as scanning electron microscope and image granularity, the coalbed methane system was divided, and its sedimentation evolution process was researched. The research results show that sand body of five types of sedimentation microfacies,whose water- and air-blocking capacity is sorted as “diversion channel