In this paper, we report the effect of annealing time on the properties of copper indium diselenide CuInSe 2 films. The CuInSe 2 thin films have been grown at room temperature by electrochemical deposition technique using two electrodes system. The as deposited films were annealed under argon atmosphere at 300 o C during 15, 30, 45 and 60 min. The structural and morphological properties of the resulting films were characterized respectively by means of x-ray diffraction (XRD) and scanning electron microscopy (SEM). The optical band gap was estimated from transmittance measurements. We have found, that after annealing, all films present CuInSe 2 in its chalcopyrite structure and with preferred orientation along <112> direction. The film annealed during 45 min exhibits better crystallinity and excellent optical properties. The SEM pictures show that the elaborated films have a uniform surface morphology with a homogeneity distribution of crystallites, the grain became higher in size with prolongation of annealing time; it lays in the range of 195 to 515Å.