Structural belt of buried hill is a building unit which shows great concentration of hydrocarbon in eastern-China faulted basin, but the research of the relationship between buried hill and hydrocarbon trap is still weak. Taking the buried hill belt of western Liaohe Sag as a research target, this paper expounds the internal structure of buried hill and the control action of accumulation from various aspects, including structural framework and active phases of inner buried hill, formation lithology and attitude, morphological unit classification and distribution framework, trapping types and hydrocarbon source conditions，hydrocarbon migration and accumulation conditions. The hydrocarbon trap is divided into palaeogeomorphology reservoir and stratigraphic hydrocarbon reservoir of inner buried hill. It establishes the “new source and old reservoir” hydrocarbon accumulation that the hydrocarbon migrates fromtop to bottom, then parallel migrates fromlowtomediumburied hill along unconformable face, at last fills in buried hill and forms the reservoir. The hydrocarbon accumulation model provides references for deep exploration activity of buried belt in Liaohe Sag.