This paper deals with the isothermal oxidation behaviors of hot-dipped Zn and Zn-0.05%Ni-0.05%V coatings at 350℃.In the investigation,the surface and section morphologies as well as the phase composition of the coatings before and after the oxidation were analyzed by means of SEM,OM,EDS and XRD.The results show that Zn-0.05%Ni-0.05%V coating effectively restrains the Fe-Zn reaction and the extra-thickness growth of ζ phase,that both the Zn and the Zn-0.05%Ni-0.05%V coatings are composed of ZnO and FeZn8.87 after being oxidized at 350℃ for 150h,that the kinetic curves of isothermal oxidation of the coatings mainly obey the parabolic rate law,and that the Zn coating possesses large oxidation mass gain due to the massive holes in it,while the Zn-0.05%Ni-0.05%V coating is of strong oxidation resistance owing to the formation of dense microstructure.