The microstructures of Al-Zn-Si-RE alloy coatings prepared by hot dipping and hot spraying were studied by SEM and EDS,the corrosion behavior of the coating in sodium chloride solution were studied by means of electrochemical testing technology.The corrosion mechanism of the coating was discussed,and the influence mechanism of different processes on the performance of the coating was clarified.The results showed that:1)Both hot spraying and hot dipping alloy coatings had the protective effect of sacrificial anode,and the protective effect of hot spraying alloy coatings was more remarkable.2)The shielding effect of the coating could be greatly improved when there was a dense corrosion product film on the surface of the hot-dipped and hot-sprayed coatings.3)Impedance spectroscopy analysis showed that there was a pitting corrosion stage in the thermal spraying coatings,but there was no pitting stage in the hot dipping coatings.With the corrosion proceeding,corrosion products were continuously generated on the surface of thermal spraying coatings,and the corrosion resistance of the coatings was improved.At the end of the experiment,it was still in the early and middle stages.The low frequency capacitance resistance of the hot-dip coatings presents Wurburg diffusion impedance characteristics,and then the coatings lose the anti-corrosion ability basically.