CuInS 2 absorber thin films were prepared by spray pyrolysis deposition at different substrate temperatures (250°C, 300°C and 350°C) using an aqueous solution of CuCl 2 , InCl 3 and SC(NH 2 ) 2 at a precursor molar ratio of Cu:In:S=1:1.25:4.5. The effect of the substrate׳s temperature on the structural, morphological, optical and electrical properties of CuInS 2 thin films was investigated. The X-ray diffraction patterns showed that CuInS 2 has a tetragonal structure. The results show that the films deposited at 300°C have improved electrical conduction and photocurrent values. When increasing the substrate׳s temperature the absorbance decreases while the band gap energy increases, as a combined effect of crystallinity, morphology and deviation from stoichiometry.