CuInS2 thin films were prepared on heated glass substrates by ultrasonic spray pyrolysis method. Structure, surface morphology and properties of films with different Cu/In ratios have been investigated. X-ray diffraction (XRD) analysis demonstrated that as-prepared CuInS2 thin films with chalcopyrite structure have a preferential orientation along the (112) direction. SEM study shows films are relatively dense and smooth, but the much bigger grains and the large coherent agglomerates appear in films (Cu/In>1.25) due to the appearance of phase Cu2S. CuInS2 thin film (Cu/In=1.25) has a strong visible absorption and its energy band gap comes up to 1.45eV.