The fixation of SiO2 nanoparticles into nanopores arrays of an anodized aluminum (Al2O3/Al) substrate was carried out using a sol-gel electrophoretic deposition technique in an aqueous SiO2 sol. Nanosized SiO2 particles can be easily incorporated into the pores of anodized aluminum prepared in a H3PO4 solution, but not into the pores prepared in a H2SO4 solution because of the difference in the pore diameters. It was confirmed that the particles in suspension were incorporated without applying an electric field. This result was due to the dissimilarity in the surface charges of the particles and anodic oxide film. (C) 2004 The Electrochemical Society.