Non-Line-of-Sight (NLOS) Underwater Wireless Optical Communication (UWOC) is mainly realized through the air-seawater interface reflection or the scattering of light by particles in seawater. It can effectively solve the link alignment issues of Line-of-Sight (LOS) underwater wireless optical communication. This paper summarizes the research progress of NLOS UWOC technology in the aspects of channel model, simulation and experiment. At present, scholars mainly explore the effects of water quality, wave, turbulence, modulation technology, receiving and sending terminal configuration on the performance of NLOS UWOC link. Few scholars have studied the effects of complex hydrodynamic and water quality factors, non-linearity of light source, non-linearity, sensitivity and noise of detector on the performance of NLOS UWOC and effective solutions. Therefore, it is necessary to carry out more in-depth channel model, simulation and experimental research in the future, so as to promote the development of NLOS UWOC technology.