This study combined anodic oxidation with chemical impregnation method to prepare Al2O3/cerium oxide composite films. First, the aluminum was anodized in 49 g/L sulfuric acid, then the anodized aluminum alloys were impregnated in the solution which contained 2g/L Ce(NO3)3?6H2O, 20mL/L H2O2 at 50℃ for 30min. And the effect of different concentrations (0 g/L, 0.25 g/L, 0.5 g/L, 1 g/L, 1.5 g/L) of 1H-Benzotriazole (BTA) on corrosion resistance of Al2O3/cerium oxide composite films was researched. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), electrochemical workstation was used to characterize the properties of the composite films. The results showed that when the concentration of BTA was 0.5g/L, the deposition effect of cerium ions was best. At the same time the surface uniformity and smoothness of composite films were both enhanced. And the resistance corrosion of composite films was increased mostly.