Abstract: In order to make clear the accumulation patterns of mid?deep natural gas in Dongfang area of diapir zone in Yinggehai basin,this paper studied the geochemistry, distribution of natural gas in high temperature and high pressure zone, and their relationship with gas accumulation based on the researches of diapir activity, using the geochemical analysis technology. The results indicate that there exist three types of thermogenic gases mainly generating from Meishan formation, including the matured coal?related gas, the high?matured and CO2?bearing coal?related gas, and the high?matured and CO2?rich coal?related gas; there are multistage mixed charging natural gases in high temperature and high pressure zones in diaper core and near it, which are characterized by strong late reworking, and there is a large amount of early charging gas in D13?2gas field; such a distribution and charging period in the diapir belt and surroundings are closely related to the diapir activity intensity differences. The influencing range of Diapir D1?1is about 10km, beyond which the quality of natural gas is getting better, and dominated by alkane?rich gas