Abstract: The natural gas from well AK1 was analyzed by multipe analytical methods in this paper.At the same time,the thermal-pressure simulation method was introduced to perform a series of gas-producing simulation experiments on many kinds of source rocks,and the simulated gas was compared with the natural gas from well AK1.The results revealed that the natural gas of well AK1 originated from dry gas formed in the postmature stage of the Carboniferous-Permian in the study area.Based on the organic inclusion analysis and the authigenic illite dating and combined with sedimentary and tectonic evolution analy-sis,the authors suggested that the natural gas of well AK1 was a result of late pool formation and staged gas accumulation and mainly congregated gas formed during the end of the Late Tertiary and the Quaternary.This result will be of important directive value for the further exploration of southwest Tarim area.