Shehejie Formation of Dongying Sag develops many lithologic reservoirs.The formation and distribution of these lithologic reservoirs are controlled by many graphic factors,including the types of structural belts,the types of dispositional system tracts,the types of reservoir facies,the conditions of source rock and the condition of the temperature-pressure,etc.Through the comprehensive analysis of the characteristics of the lithologic reservoirs in Shehejie Formation of Dongying Sag,it is held that whether the lithologic traps can form oil reservoirs is usually controlled by four major factors:hydrocarbon migration pathways,power condition of fluid flow,physical properties of reservoirs,and the sealing condition of sandbodies.But the formation of the lithologic reservoirs in Niuzhuang Subsag is controlled by three factors.