The corrosion resistance of anodic oxide film sealed with alumina sol can improved. Cu2+ was put into the alumina sol so that antibacterial property was endowed to the sealed film. Composition, morphology and corrosion resistance of sealed film doped with Cu2+ were studied by DSC, EIS and SEM etc. The film sealed by doping Cu2+ in sol has less and narrower crack on the surface than the one without Cu2+. The gel without Cu2+ has more chemical reaction and phase transition than that with Cu2+ in the heating process observing from the DSC curve, which results in more cracks on the surface of sealed films without Cu2+. Sol doped with Cu2+ can enhance corrosion resistance inferred from the polarization curve, in a way. The films sealed by sol with Cu2+ have a good antibacterial on Staphylococcus aureus. The antibacterial rate is more than 99%. The results show sol doped Cu2+ not only improve corrosion resistance but also have antibacterial property.