Zinc oxide (ZnO) thin films are produced by the spray pyrolysis method on glass substrates at 450 °C. The films are characterized using X-ray diffraction (XRD), and UV-VIS transmittance spectroscopy. XRD pattern showed that the films are polycrystalline with hexagonal (wurtzite) structure. Transmittance was measured at room temperature in the wavelength range 350-1100 nm, and used to deduce the absorbance. The fourth derivative of the absorbance is used to detect the peaks in the near band edge region. Several peaks are found in the region of interest, from which are the free exciton peaks A, B, and C, bound exciton peaks related to defects and impurities, and very weak peaks assigned to longitudinal optical phonon replicas. These results are important for solar cells, room temperature UV-laser, and other photonic and optoelectronic applications.