There has been relatively little research on the natural gas genesis in the east of Penyijingxi Sag in Junggar Basin, and the lack of comparative analysis of gas sources directly restricts the evaluation of the region"s natural gas exploration potential. Based on gas samples from the Sangonghe Formation of the Jurassic, organic geochemical tests were conducted to systematically analyze the genesis, source, and accumulation process of natural gas. Research shows that the gas components of the Sanguohe Formation in the east of Penyijingxi Sag are mainly organic thermal origin, with methane being predominant, accounting for an absolute advantage with a relative content ranging from 80.44% to 92.19%. The drying coefficient of natural gas is between 0.83 and 0.95, and it is mainly wet gas. The natural gas is mainly of coal-type, with a small amount of oil-type and mixed gases. Among them, coal-type gas is the product of the lower Wuerhe Formation source rock in the mature high mature stage (0.69% < Ro < 1.49%), and oil-type gas is the product of the Fengcheng Formation source rock in the mature stage (0.75% < Ro < 0.96%). In the slope belt, where only Yanshanian strike-slip faults are developed, the natural gas is solely sourced from the Lower Wuerhe Formation, with two accumulation events. In contrast, the bulge belt features a "relay transmission" between basement faults and strike-slip faults, resulting in contributions from both source rock intervals, with the Lower Wuerhe Formation accounting for over 69% and three accumulation events. During the Paleogene, the early charged hydrocarbons underwent south-to-north adjustment, establishing a natural gas accumulation model characterized by hydrocarbon supply from Permian source rocks, differential charging in the Sangonghe Formation reservoir, and adjustment during the Himalayan period.