The electrochemical behaviour of sol-gel prepared nanocomposite coatings has been investigated to prove their corrosion protective capabilities. Amorphous zirconia (5 nm) and crystalline ceria (10 nm) nanoparticles were embedded in the sol-gel matrices with solid contents between 8 and 20 wt.%. The sol-gel coatings were applied to AA 2024 substrate. Additionally, part of the sol-gel coated samples was covered by two extra layers of industrial paint system provided by EADS Co. for additional protection ability. The thicknesses of the prepared single sol-gel coatings and the top-coated samples varied within 13 to 19 and 40 to 78 µm, respectively. The corrosion protection performance of these samples was determined by means of electrochemical measurements, including voltammetry and electrochemical impedance spectroscopy.