In this work we studied the influence of the dopant elements and concentration on the properties of ZnO thin film deposited by spray pyrolysis. The results show that the doping affects the thin films properties mainly the electrical ones, function of dopant concentration and nature. The most important changes were observed for films doped with 1 at% of indium which exhibit a resistivity of 1.9101Ocm associated with a transmitance of 90%. After the annealing treatment, the resistivity of the film decreases to 5.9103Ocm without significative changes in the optical properties. The films were also used to produce amorphous silicon solar cells where the best results were obtained for ZnO : In. r 2002 Elsevier Science Ltd. All rights reserved.