The electrochemical syntheses of polypyrrole (PPy) and poly(pyrrole-co-o-anisidine) were achieved on 3102 aluminum alloy (Al) from 0.1 M monomer (pyrrole:o-anisidine, 8:2) containing 0.4 M oxalic acid solution using the cyclic voltammetry technique. The synthesized films were characterized by FT-IR spectroscopy. The thermal stability of films was determined by thermogravimetric analysis (TGA) technique. Surface morphologies were characterized by scanning electron microscope (SEM) images. The potential of zero charge (pzc) of Al was determined using electrochemical impedance spectroscopy (EIS). The corrosion behavior of samples was investigated with open circuit potential (E-ocp)-time. EIS, and anodic polarization techniques. It was found that copolymer coated Al provides better barrier property against of corrosion in 3.5% NaCl solution. (C) 2010 Elsevier B.V. All rights reserved.