Lithium niobate(LiNbO3) on insulator(LNOI) is a promising material for integrated photonics, owing to its unique properties of wide optical transparency window, high refractive index, large second order nonlinearity and large piezoelectric response. The integrated LN material, featuring sub-wavelength scale light confinement and high integration of optoelectronic components, has the potential to enable higher performance, lower cost and entirely new devices and applications, and revolutionize optical communication and microwave photonics. This review focusses on the current progress of LNOI electro-optic modulator, LNOI acousto-optic(AO) modulator and LNOI electro-optic frequency comb, and briefly discusses the challenges meeting from fabrication and system realization.