In this work Cd2SnO4 polycrystalline thin films with cubic phase were deposited on glass substrates by the sal-gel technique starting from the mixture of two simple precursor solutions of CdO and SnO2, obtained at room temperature. Both solutions were prepared using metallic salts, cadmium acetate and stannous chloride. The Sn atomic concentration percentages (X) in the precursor solution with respect to Cd (1 - X) were 16, 25, 29, 33,36 and 40. The films were sintered at 550 degrees C in air and, after that, exposed to two different annealing treatments, 96/4N(2)/H-2 gas mixture and vacuum, at 350 degrees C and 550 degrees C, respectively. X-ray diffraction patterns of the films without annealing showed three types of films: i) for X < 29 at%, the films were constituted of CdO+Cd2SnO4 crystals, ii) for X=29 at% and X=33 at%, Cd2SnO4 polycrystalline thin films were obtained, and iii) for X > 33 at%, Cd2SnO4+ CdSnO3 crystals were formed. Cd2SnO4 films maintained the spinel-type crystalline structure of the Cd2SnO4 after the annealing processes. On the other hand, Electron Dispersion Spectroscopy measurements revealed that Cd2SnO4 films obtained at X=29 at%, without annealing, had a Cd/Sn ratio nearest to the one of the Cd2SnO4 compounds. With and without annealing Cd2SnO4 films showed high optical transmission similar to 85% in the 500 nm < lambda < 1500 nm range. A minimum resistivity value was around 2 x 10(-3) Omega cm, which was obtained for Cd2SnO4 films (X=33 at%) annealed in vacuum at 550 degrees C, and a direct band gap energy value of 3.55 eV. As a test of the quality of these films as transparent electrodes, Au/Cu2Te/CdTe/CdS/Cd2SnO4/glass solar cells were obtained with average efficiency of 10.7%. (C) 2014 Elsevier B.V. All rights reserved.