The utility model discloses a retractable's expanded metals breakwater, prevent the ripples unit including a plurality of, every prevents that the ripples unit includes a kickboard, has seted up a plurality of rectangular holes along the board rectangle in the kickboard, is provided with in the rectangular hole to the decurrent reinforcing bar of kickboard bottom surface extension net, and the reinforcing bar net sets up along the direction of propagation of wave, and rectangular hole length direction's both sides are provided with the buckle that is used for fixed reinforcing bar to net, a plurality of is adjacent to be prevented linking to each other through the hinge between the kickboard of ripples unit, has linked firmly the anchor chain on being located the kickboard at both ends, prevents with a plurality of that the ripples unit connection forms the linear type breakwater through the anchor chain.