The invention aims at providing a hull cleaning system. The hull cleaning system comprises a control device, a wall-climbing robot, a super-pressure pump and a motor, wherein the control device comprises a control unit; the control unit is respectively connected with the wall-climbing robot, the super-pressure pump and the motor; the super-pressure pump is used for supplying water for the wall-climbing robot through a water outlet pipeline; the wall-climbing robot comprises a main body, a moving device, an electromagnetic adsorption device and an oscillation cavitating jet cleaning device; the moving device is arranged on the main body and is used for moving the main body; the electromagnetic adsorption device is used for absorbing the main body onto a hull; a suction cavity is arranged on the main body in an embedding way; the oscillation cavitating jet cleaning device is arranged in the suction cavity. The hull cleaning system has the beneficial effects that 1, hull cleaning can be completed in a sailing process without enabling a ship to berth at a dock; 2, an intermediate step of draining off the water all over a body of the hull is omitted, so that cleaning cost is lowered; 3, rust dust and dirt produced in the cleaning process are recovered after cleaning, so that the hull cleaning system is excellent in environmental protection performance; 4, cleaning degree can be controlled and detected, so that a better cleaning effect is achieved.