Abstract ：Using ZnO mixed with Al2O3 (3wt%) as target, ZAO thin films were deposited on glass substrate by DC magnetron sputtering，the influences of the deposition parameters on the crystallization behavior as well as optical properties of ZAO films have been investigated．The X-ray diffraction measurements revealed that ZAO film was polycrystalline with the hexagonal crystal structure and has a strongly preferred orientation of c axis perpendicular to the substrate surface. The structure and optical transmittance of ZAO films were obviously influenced by the substrate temperature and oxygen partial pressure. The obtained film exhibits optimal structure and optical transmittance of 86.5% with the substrate at 200℃ and the oxygen and argon ratio was 1%.