Thin film LiNbO3 modulator has become a hot spot in the industry in recent years because of its small size, high bandwidth, low half wave voltage and other advantages. In this paper, the research progress on waveguide structure, electrode structure and bias point control technology of LiNbO3 modulator were reviewed. The performance of three different waveguide structures, including planar buried waveguide, ridge waveguide and photonic crystal waveguide, were analyzed. The characteristics and design considerations of the lumped and traveling wave electrode structures of LiNbO3 modulator were discussed. The advantages and disadvantages of the power method and the pilot method in the bias point control of electro-optic modulator were compared, as well as the related research results. Based on this, the key technologies and future research directions for realizing the LiNbO3 modulator with smaller volume and higher bandwidth were further analyzed.