Lithium niobate crystals have many physical properties, such as nonlinear effect, electro-optic effect, acousto-optic effect, photorefractive effect, piezoelectric effect, and pyroelectric effect, et al. They have been widely used in surface acoustic wave (SAW) device, electro-optic device, acousto-optic device, and so on. After over 60 years of development, lithium niobate single crystal is still active in the material science and application. With the continuous development of material properties, plenty of new functions, new devices, and new applications come out. Especially in recent years, the development of lithium niobate single crystal films provides a key material for the new generation of information and communication technology in the aspects of thin film filter and integrated electro-optic modulation. In this review paper, the growth of lithium niobate crystals, the preparation of crystal films, and the new applications of lithium niobate crystals in recent years are briefly reviewed, and the prospective application of lithium niobate crystals is discussed.