ZrO2 and ZrO2-PVP sol was obtained by hydrothermal synthesis. And the thin films were prepared with spin coating method. ZrO2 thin films were characterized or examined by many kinds of instruments. Fourier-transform infrared spectroscopy was employed and some infrared absorption peaks weakened when the heating temperature increased. And 1-on-1 laser-induced damage threshold tests on ZrO2 films were carried out. Refractive index and thickness of the ZrO2-PVP films were measured by means of automatic scanning spectroscopic ellipsometer and the refractive index of ZrO2 -PVP film changed with the addition of PVP content.