Abstract: In view of the geological problems such as low drilling degree,big reservoir variances and unclear distribution of hydrocarbon reservoirs in Fuxin sag,through 3 typical structures analysis of Dongliang.Xiaohujia and Qinghemen,main controlling factors of hydrocarbon accumulation in this area have been proposed.Besides the basic factor of source conditions,the most important reservoirs of good properties are lower member of Shahai formation and upper member of Jiufotang formation.Structural traps formation is controlled by Yanshan movement in later period of early Cretaceous,while the reservoir distribution is determined by trap development zones of anticline,fault- anticline or fault- nose structures.From the analysis of exploration potential,oil and gas geological conditions and reservoir accumulation regularities,two favorable exploration targets,namely north faulted- nose trap in Yimatu and eastern faulted- anticline trap in Aiyoudong.have been predicted.