The aim of this work is to study the effect of the deposition potential on the properties of copper indium diselenide CuInSe2 films. The CuInSe2 thin films have been grown on well-cleaned indium tin oxide (ITO) coated glass substrate by electrochemical deposition technique using two-electrode system. The deposition potential is ranged between -4 and -8 V. The as deposited films were annealed under argon atmosphere at 300 degrees C during 30 min. The structural and morphological properties of the resulting films were characterized respectively by means of X-ray diffraction and scanning electron microscopy. The optical band gap E-g and the urbach energy E-00 were calculated from the transmission spectra data. The lattice constant and the structural parameters such as crystallite size (G(s)), dislocation density (delta), and strain (epsilon) were calculated from the XRD pattern. We have found that after annealing, only the films deposited at -6 V, -7 V and -8 V present CuInSe2 in its chalcopyrite structure and with preferred orientation along the [112] direction. Also, it has been found that the film deposited at -7 V has better structural and optical properties. (C) 2011 Elsevier B.V. All rights reserved.