A dynamic metal-anode flow battery energy-storage system includes a discharge module, a charging module, and a delivery device. The discharge module includes a plurality of discharge reactants to be oxidized to discharge electric energy. The charging module is electrically connected to the discharge module and includes at least one electrolysis device and at least one removal device. The electrolysis device includes a conductive member which is to be energized with electricity, such that a plurality of electrolysis products having the same material with the discharge reactants are adhered to a surface thereof. The removal device includes a scraper adapted to remove the adhered electrolysis products from the surface of the conductive member. The delivery device is adapted to deliver the electrolysis products into the first electrolyte as the discharge reactants, and deliver the discharged products into the second electrolyte as the electrolysis reactants.