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The shale in the upper part of the 4th member of Paleogene Shahejie Formation in the Dongying Sag of Bohai Bay Basin can be divided into two lithology types: calcareous mudstone and argillaceous limestone. The differences of organic matter abundance, oil-bearing properties, reservoir properties and movable shale oil in the different lithologies were investigated using X-ray diffraction, microscopic observation, geochemical analysis, porosity tests and mercury injection. The calcareous mudstone has relatively higher organic matter abundance and better oil-bearing properties than the calcareous mudstone. The calcareous mudstone has relatively higher porosity, but the pore throats are generally smaller, while the argillaceous limestone porosity is relatively lower with more large pore throats. The shale oil mobility in the calcareous mudstone and argillaceous limestone was compared using the oil saturation index, mineral adsorption capacity for crude oil and clay mineral transformation degree. The shale oil in the argillaceous limestone has better mobility than the shale oil in the calcareous mudstone.