AbstractTransparent lithium niobate (LiNbO3) with thickness from 0.1 - 1.2 μm were made on silicon, fused silica, and sapphire substrates by the sol-gel processing. Alkoxide solutions were used as starting materials. X-ray diffraction has been used to confirm the crystallization of the films. Refractive index, dielectric and ferroelectric properties of LiNbO3 films were studied. Absorption spectra of films of LiNbO3 and LiNbO3 with doping of different amount of Fe (0.1 - 2.5mol%) were measured. Short-circuit photocurrent measurements revealed both transient and steady state components attributed to a pyroelectric effect and a bulk photovoltaic effect respectively. Epitaxial growth of LiNbO3 thin film on sapphire(012) substrate by sol-gel method was also obtained.