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A large-scale hydrological observational network has been maintained in the tropical Indian Ocean since 2010 by the South China Sea Institute of Oceanography， Chinese Academy of Sciences （CAS）. This paper reviews the research progress on the circulation dynamics over recent years based on the CAS observations. The results reveal an "ocean wave bridge in the eastern boundary". On the equator， the currents in the upper layer， the thermocline， and the middle layer are significantly modulated by the equatorial Kelvin and Rossby waves directly forced by equatorial winds and reflected from the eastern boundary， which effectively transport energy horizontally and vertically. Off the equator， the currents are still regulated by the equatorial dynamics， as equatorial-origin wave signals transmit energy there relying on the eastern boundary in the form of coastal Kelvin waves and reflected Rossby waves. Under the support of the dynamic fulcrum of the eastern boundary， the ocean wave bridge is thus an energy belt， which links generation and variation of the circulation in the tropical eastern Indian Ocean. In addition to the internal factor， contributions of external factors such as large-scale climate mode on the circulation are also discussed. The dynamic framework of ocean wave bridge will provide scientific enlightenment for further research on the characteristics， changes， and effects of the tropical Indian Ocean circulation.