Spray pretreatment equipment mainly utilizes the principle of chemical reaction to treat workpieces. Hanging on the conveyor line of the workpiece in turn into the pre-treatment equipment shed body, the corresponding process of treatment fluid in the pump suction, spray pipeline distribution and nozzle atomization, according to a certain pressure, flow and temperature uniform spray on the surface of the workpiece, the surface of the workpiece oil, grease, oxidized skin, dust and sundries are cleaned; and then the substrate and the treatment of the tank liquid chemical reaction for the workpiece for the ultimate coating to provide excellent Anti-corrosive substrate base layer.