The invention discloses a self-flow electromagnetic oil pumping device which adopts the structure that a pump shell and an electromagnetic coil are mounted in a buoyancy shell; the electromagnetic coil is arranged outside the pump shell; the lower end of the pump shell is fixed in the buoyancy shell; an oil outlet valve is fixed in a central hole in the pump shell; an iron core spring and an iron core piston are arranged in the pump shell; the iron core spring presses against the iron core piston; oil inlet passages in an oil inlet cavity and an extrusion cavity are sealed with sealing cones or sealing balls; an oil-dividing limiting plate is fixed in a limiting hole in the upper end of the iron core piston; and another sealing cone or sealing ball is mounted in an inner conical hole in the iron core piston. The self-flow electromagnetic oil pumping device is compact in structure, and strong in power, floats on edible oil or industrial oil and can rise or fall automatically along with the change of an oil level when being used for pumping the oil, and has the advantages that water and impurities at the bottom of an oil tank or an oil depot used for storing the oil cannot enter an oil pump when the self-flow electromagnetic oil pumping device is used for pumping the oil; and under the condition that an oil outlet hole is lower than an oil inlet hole, the oil still can flow freely to be transported when a power supply is turned off.