The invention relates to a novel hydraulic cutter device for cutting multi-layer casings. The novel hydraulic cutter device for cutting the multi-layer casings is used for the deep-water wellhead wellabandonment operation. The wellhead casings are cut by the novel hydraulic cutter device, so that wellhead devices are convenient to recycle. According to the technical scheme, drilling fluid pushesa piston to move down, and then the piston drives a cutter to rotate around a pin, so that the cutter cuts the casings; when cutting of the cutter is completed, a piston circumferential through hole communicates with a limiting rod radial through hole, and at this time, the drilling fluid pressure has an obvious pressure difference, and whether the casing cutting is completed or not can be judgedaccording to the fluctuation of the drilling fluid pressure; and a blade supporting structure is additionally arranged on the end portion of the cutter to realize smooth recovery of a blade. The novelhydraulic cutter device for cutting the multi-layer casings has simple operation, whether the casing cutting or not is completed can be effectively judged, the cutting of the multi-layer casings withdifferent diameters can be achieved by adjusting the relative distance of pressure relief holes.