Abstract: As crucial basis for marine research, global ocean circulation forecast systems can provide a full range of support for ocean disaster prevention and mitigation, navigation safety and ocean climate research. An ocean circulation forecast system mainly consists of ocean circulation model and data assimilation system. On the basis of ocean circulation research, a number of ocean circulation models have been developed. Among them, the NEMO model released by Europe and the HYCOM model released by the United States are widely used. Based on the two models, many operational ocean forecast systems have been constructed with optimal interpolation and three-dimensional variational (3Dvar) assimilation methods. The LASG/IAP Climate System Ocean Model (LICOM) developed by the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) at the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, has greatly enhanced China's autonomy in constructing coupled models and forecast systems, and has realized the assimilation of multiple marine data in combination with the ensemble optimal interpolation method. In China, the relatively-late initialization of operational ocean forecast and real-time operational products has resulted in the unmet needs from ocean navigation and smart ocean meteorological services. Currently, the NEMO model is employed in the released Chinese Global Oceanography Forecasting System (CGOFS). Based on the investigation into the global ocean circulation forecast systems, primarily into the research and development as well as operational application of the NEMO, HYCOM, and LICOM models, this study makes it possible to further grasp the current situation of ocean circulation forecast model development both at home and abroad. This is of great significance for China to build a realtime marine operational system, improve the quality of realtime marine products, and implement the strategy of building a strong maritime country.