Recently important exploration discovery of natural gas has been obtained in high-temperature and overpressure intervals in Dongfang area, Yinggehai Basin, South China Sea. In this study, chemical component and stable carbon isotopic compositions were analyzed for 72 natural gas samples collected from different gas fields and different production formation, which exhibited widely different distribution characteristics. In southwest region such as XY1-1/XY13-1, natural gas with low CO2 content and low maturity appeared in shallow intervals such as Huangliu Formation and Meishan Formation whilst gas with high CO2 content and high maturity occurred in middle-deep intervals such as Huangliu Formation and Meishan Formation. However, in northeast region such as XY-1S/XY13-2, natural gas just presents reverse distribution characteristics. This kind of distribution is attributed to the effect of diapir action mainly occurred in the XY1-1 region. Based on the geochemical characters of natural gas and evolvement of diapir, two gas accumulating models in low energy area and high energy area are put forward to explain the distinct characteristics occurred in different gas fields. Locating faraway from diapirs, XY1-1S/XY13-2 are rarely influenced by the activity of diapirs. Gas generated by source rock early with low CO2 content and low maturity transports through micro-fractures into middle-deep intervals such as Huangliu Formation and Meishan Formation. Because of the lower energy influenced by the diapirs, gas reservoirs formed early were protected. Subsequently, faults induced by activity of the diapirs led the gas with high CO2 content and high maturity generated in the late stage up to shallow interval such as Yinggehai Formation. There may exist some difference in natural gas conduit system between shallow intervals and middle-deep intervals. On the contrary, XY1-1/XY13-1 are located near to the XY1-1 diaper with high energy, the migration and accumulation of natural gas strongly influenced by intensive activity of the XY1-1 diapir. As a result, gas accumulated early with low CO2 content and low maturity was destroyed and re-migrated up to shallow interval such as Yinggehai Formation and gas generated afterward with high CO2 content and high maturity mainly get into the middle-deep intervals such as Huangliu Formation and Meishan Formation. These two gas accumulating models explain the complicated distribution of the gas in Dongfang area commendably and thus provide strategy guidance for the exploration of high quality natural gas of low CO2 content in Yinggehai Basin.