Abstract: One of the uses of fluid inclusion enclaves analysis in petroleum geology is to utilize inclusion enclaves in diagenic minerals in inferring hydrocarbon migration path,calculating injection time and determin-ing injection direction.The patterns of homogeneous temperature of hydrocarbon inclusion enclaves in the Xinglongtai reservoir,as a whole,are characterized by normal unimodal or asymmetric unimodal distributions,and the major peak temperatures range from 80℃ to 100℃,which reflect that,the hydrocarbon inclusion enclaves in different samples are of the similar formation process.In addition,inclusion homogeneous temperatures in a few wells display a bimodal distribution pattern,which may imply that,there exist at least 2 stages of inclusion formation.Studies on the burial-heat evolution history shows that,hydrocarbon injection period in the Xinglongtai reservoir is 3-35 Ma ago,which can be divided into 2 major stages:27-35Ma and 3-24Ma,and the former is the main hydrocarbon injection stage.Researches also show that,the direction of hydrocarbon injection is from the east to the west.There are 3 pool-forming stages:a)A small amount of hydrocarbon migrates into the embryonic trap in the late Es³,after which the temporary uplift in the end of Es³ results in oxidation for part of the hydrocarbon in the incipient reservoir,forming black asphalt;b)The Es²-Ed stage is the major hydrocarbon accumulation period;c)Hydrocarbon gene-(ration) intensity is relatively weak since the late Tertiary.Hydrocarbon in the reservoir is preserved,which is attributed to the excellent mudstone cap of the overlying Es³⁺⁴.