Abstract: Yingmaili-Yaha buried hills are of abundant petroleum resources and good petroleum geologic conditions. The hydrocarbon was dirived from the Manjiaer sag marine facies in the south of the buried hill and the Kuqa depression terrestrial facies in the north. Two regional caprocks, the Middle- to Upper-Ordovician mudstone and the Cretaceous Kapushaliang Group mudstone play the most important roles in formation of hydrocarbon reservoir. The oil-gas distribution in the buried hill is chiefly controlled by reservoir space which is mainly featured by cavities and cracks. The hydrocarbon accumulation pattern is controlled by the lateral distribution characteristics of these cavities and cracks. The hydrocarbon accumulation pattern in the Yingmaili-Yaha buried hills is more complex because the reservoir has more lateral heterogeneity and less pore space and continuity, as compared with the Lunnan buried hill. Generally speaking， these buried hill pools are characterized by massive oil accumulation and bottom water. The oil-gas-water interfaces have different depths due to the connected tube effect in different parts of fracture and cave reservoirs and the displacement process of oil and gas controlled by the reservoir space size.