Electropolymerization of O-phenylenediamine (o-PD) on Pt-electrode from a deoxygenated aqueous acid medium was carried out using cyclic voltammetry technique. The kinetic parameters were calculated by means of electrochemical data. The experimentally obtained kinetic equation was R-P,R-E = k(E) [monomer](1.19) [acid](1.23) [electrolyte](0.87) from the value of the anodic current density using cyclic voltammetry technique. The apparent activation energy (E-a) is found to be 28.34 kJ mol(-1). The polymer films obtained have been characterized by X-ray diffraction, elemental analysis, scanning electron microscopy, H-1-NMR, C-13-NMR, UV-visible, and IR spectroscopy. The mechanism of the electrochemical polymerization reaction has been discussed. TGA is used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 3695-3706, 2009