Cores, logs, seismic profiles, rock flakes, laboratory data and other information were studied for the microfacies of the Shan1 & Shan2 Formation in Sulige gas field, Sudong Block. The results show that the gas fields in northeast Shan1 & Shan2 Formation occur in a meandering river and floodplain depositional system. The main sedimentary facies include the microfacies of meandering rivers, point bars, floodplains, interdistributary bays. Source supply is relatively abundant, and formations a certain thickness of massive sand meandering channel deposits.