Indium (III) oxide (In2O3) thin films have been obtained after heat treatment of In(OH)3 precursor layers grown by a potential cycling electrodeposition (PCED) method from a dimethylsulfoxide (DMSO) based electrolytic solution onto fluorine-doped tin oxide (FTO) coated glass substrates. X-ray diffraction (XRD) measurements indicate the formation of a polycrystalline In2O3 phase with a cubic structure. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed a smooth morphology of the In2O3 thin films after an optimized heat treatment had been developed. The surface composition and chemical state of the semiconductor films was established by X-ray photoelectron spectroscopy analysis. The nature of the semiconductor material, flat band potential and donor density were determined from Mott–Schottky plots. This study reveals that the In2O3 films exhibited n-type conductivity with an average donor density of 2.2 × 1017 cm−3. The optical characteristics were determined through transmittance spectra. The direct and indirect band gap values obtained are according to the accepted values for the In2O3 films of 2.83 and 3.54 eV for the indirect and direct band gap values.