Hafnium oxide (HfO2) films were investigated by many people, and were used in optical devices. The characteristics of HfO2 films were strongly affected by the preparation conditions and experimental parameters. In order to obtain good hydrophobic and optical films at low substrate temperature, HfO2 films were deposited by RF magnetron sputtering in this study. The effects of RF power, substrate temperature, the ratio of O2 to Ar pressure and W content on the optical and hydrophobic properties of HfO2 films were investigated. The results indicated that HfO2 film exhibited better hydrophobicity, higher optical energy gap and higher visible transmission as the ratio of O2 to Ar pressure increased to 0.21.