The invention discloses a dual-power automobile-mounted wet spraying machine. The wet spraying machine comprises an automotive chassis with a power system and an auxiliary frame arranged on the automotive chassis with the power system, and hydraulic supporting legs, a boom system, an electric control system, an admixture system, a dual-power jet system, an air compressor, a hydraulic oil tank, a cable drum and a pumping system are arranged on the auxiliary frame. The pumping system is connected with the dual-power jet system, and the dual-power jet system is connected with the air compressor and the boom system. The dual-power automobile-mounted wet spraying machine can be controlled in a multi-direction mode easily, work dead corners are eliminated, concrete rebound and caving are effectively reduced, and construction quality is improved. The dual-power jet system of the wet spraying machine is supplied with an engine and a dual-output-shaft motor to jet concrete, so that the wet spraying machine shakes off electricity dependence, and the application range is broadened.