Abstract: Since China's reform and opening up, great achievements have been made in the development of marine economy, which can be attributed to the effective operation of marine management structure with Chinese characteristics.The State Oceanic Administration, which has been established for 55 years, is no longer retained in China's institutional reform in 2018.The organizational structure and institutional framework of China's ocean management have been reconstructed as a whole.The functions of ocean management at the central level are allocated to many departments, and local ocean management has formed a variety of models.The role of land-sea coordination in contemporary China's ocean governance is more prominent, but it still faces the problems of inconsistent establishment of sea-related management institutions, inadequate functional allocation, and poor operation of the mechanism.In terms of the composition of governance power, the current ocean management structure has reduced the effectiveness of China's participation in global ocean governance, weakened the emphasis on ocean economic development, and weakened the grass-roots ocean management team, and the phenomenon of local government multi-management has not yet been fully resolved.In terms of function realization mechanism, the power allocation of horizontal, vertical and oblique intergovernmental relations of sea-related management institutions together constitute the overall structure of China's current ocean governance organization.However, the absence or non-existence of sea-related coordination institutions leads to the insufficient synergy of ocean management between central and local relations, land and land relations and departmental relations.In the practice of governance, agile governance, overall intelligent governance and global vision have become the development requirements and debugging paths of contemporary China's ocean management.Some large ocean provinces, strong ocean cities and large ocean cities in China have successively established independent ocean comprehensive management institutions since this year, marking that coastal areas have reshaped the ocean governance system according to local conditions and made efforts to develop the ocean economy, which has also become the proper meaning of the construction of a maritime power.