A seawater battery of dissolved oxygen type includes a battery frame (1), n pieces of metal anode plates (2), n pieces of inert cathode plates (3), current collectors and wires (5). The battery frame (1) is consisted of an upper base (6) and a lower base (7), wherein the upper base and the lower base are respectively consisted of an outer ring and a central fixing component. The fixing component is connected with and fixed to the outer ring by a connector, and n pieces of metal anode plates are inserted on the connector so as to construct a cylindrical or frustum-shaped structure. The inert cathode plates are inserted between the metal anode plates along radial direction of the outer ring, and are connected with and fixed to the outer ring and the fixing component of the upper base and the lower base. The metal anode plates are welded in series by wires constituting the anode of the battery and the inert cathode plates are welded in series by wires constituting the cathode of the battery.