Pulsed CO2 laser is used in the wet laser cleaning of rust from iron surface. By pre-spraying liquid film to the top surface, the liquid can penetrate into the rust layer due to the porous structure of the rust, so the thermal conductance and the mean specific heat of the rust layer can be improved. At the mean time, as the explosive evaporation of the liquid in the rust under laser irradiation has the effect of breaking down the rust layer, the cleaning efficiency can be efficiently increased. But it is disadvantageous that the electro-chemical corrosion of the iron will be intensified if the liquid film has some residue. Thus, the removal of the residual liquid film is a necessary operation after the first-step of cleaning. Acousto-optic Q-switched NdYAG laser is used to heat the iron surface. By adjusting the number of laser pulse, the surface temperature can be controlled. The residual liquid film is vaporized firstly, and then the oxidation process of the superficial iron layer can be accelerated. A dense film of iron oxide is formed above the iron surface. Uniform passivation is realized and the corrosion resistance of the iron is modified after laser cleaning. A device of laser wet cleaning adopting dual laser beam is designed, which can perform cleaning and passivating simultaneously.