Zinc oxide films were deposited on fused quartz wafers using sol-gel technique and by adopting the spin-coating method. The structure of c-axis oriented ZnO films measured by X-ray diffraction is mainly decided by the post-annealing temperature. ZnO films annealed at different temperatures have a high transmittance and strong UV emission peaks which were measured by UV-VIS double-beam spectrophotometer and PL spectra. It is obvious that the annealing temperature at 650℃ is the best condition for high-quality ZnO film. The thermogravimetric analysis(TGA) of the sol was carried out, and it is found that the temperature from amorphous to more ordered state is 375℃, and crystal ZnO film is helpful to the deposition of ZnO film with high quality via the sol-gel method.