By anodic oxidation,a dense oxide film was produced on the surface of CNT/2024 Al composite prepared by powder metallurgy. The effect of anodic oxidation on the corrosion behavior of CNTs reinforced Al-alloy composite was studied by salt spray corrosion test. The evolution of surface and cross section of anodic oxide film under salt spray was investigated by SEM,and its effect on mechanical property of composite after salt spray corrosion was further studied. The results show that the non-anodized samples will be corroded remarkably when exposed to salt spray,and the tensile strength and elongation will greatly decrease. By anodic oxidation,stable dense oxide film of about 2 μm can be formed on the surface of the composites. Compared with the non-anodized samples,the corrosion under salt spray can be effectively prevented,and the mechanical properties of the materials do not significantly reduce.