Zirconia (ZrO2) thin films were prepared by metalorganic chemical vapor deposition (MOCVD) using ultrasonic nebulization with new source materials, Zr(OBu)4, Zr(OBu)3(acac), Zr(OBu)2(acac)2, and Zr(OBu) (acac)3. This process is a simple and economic method to prepare oxide thin films. Zr(OBu)4 was successfully reacted with acetylacetone at a molar ratio of 1: 3. Polycrystalline thin films were deposited at a substrate temperature range from 300 to 550 °C. The substitution of alkoxy radicals by acetylacetone made the deposition rate higher and insensitive to substrate temperature. The films deposited below 450 °C mostly had a monoclinic structure, and those deposited above 450 °C had a tetragonal structure. The measured optical energy band gap of zirconia film was 5.32 eV.