The invention provides a preparation method of an active carbon composite graphene foamed electrode plate. The preparation method comprises the following steps of (1) adding graphite oxide and polypropylene to a ball grinding machine for ball grinding, and then adding the mixture after ball grinding to a mixed solution of ethanol and water for ultrasonic dispersion to form a suspension liquid; (2) immersing foamed nickel in the abovementioned suspension liquid, drying a solvent, placing the solvent a muffle furnace protected by a mixed gas of hydrogen and nitrogen for reaction, and naturally cooling the product after complete reaction; (3) immersing the abovementioned product in a hydrochloric acid for reaction, and obtaining foamed graphene after complete reaction; and (4) adding active carbon to absolute ethyl alcohol, performing ultrasound to form a suspension liquid, dropwise coating the ethanol suspension liquid containing the active carbon on the foamed graphene, and performing rolling after drying and cooling to obtain the electrode plate. In the electrode plate prepared by the method, a binding agent and a conductive agent are not needed to be added to a conventional electrode plate, and the material cost is reduced.