Both the strength of an applied biased electrical field and the substrate temperature were found to have significant effect on the oriented growth of LiNbO3 thin films prepared by pulsed laser deposition technique.At a substrate temperature of 600℃ and an applied electrical field of 7V/cm,completely (001) oriented LiNbO3 films were deposited on silica and other amorphous substrates successfully.The physical background of the oriented growth of ferroelectrical films induced by low electric field was analyzed in terms of nucleation and growth theory of ferroelectrics with spontaneous polarization in electrical field and the deposition temperature effect on the intensity of spontaneous polarization of the ferroelectrics.