ZnO thin films and ZnOSiO2 composite films were deposited on glass substrates by solgel method. Atomic force microscope images showed that ZnO nanoparticles havd spherical shape of relativly small size. The ultravioletvisible transmittance spectra showed that the transmittance of ZnOSiO2 composite film is about 85% in visible range and the transmittance begins to drop at about 330 nm and reaches zero around 290 nm. Due to quantum effect, the absorption edge has an obvious blue shift. Photoluminescence spectra measurement indicated that ZnOSiO2 composite film excited by a Xe lamp with different wavelength has a UV emission around 290 nm coming from combination of free excitons, which is in agreement with the ultravioletvisible transmittance measurement result. Meanwhile, two photon and three photon absorption and upconversion luminescence were observed in the ZnOSiO2 composite film.