This study aims to examine the formation and maritime network in East Sea Rim with the particular reference to the development of port institutions by central governments, strategies by local government. So as to achieve this aim, it take a careful look at the institutional and strategic characteristics which influence the formation of East Sea Rim maritime networks. During the colonial period, the ports had been compelled to open to become a base for the exploitation of goods and to form the compulsory maritime networks to home ports. In the case of the Northeastern China, since they do not have an exit to go to sea, they have been fostering the derived maritime networks to take use of the ports in Russia and North Korea, connected to their gate city. While the central governments in China and Russia have led to build up the port infrastructure, they have been supporting the local governments. During the globalization era, Korea and Japan have made attempts to reinforce the capacity of their ports by introducing institutions by the central governments and to provide administrative and economic incentives by local governments in order to construct the selective maritime networks. In this regard, maritime networks in the East Sea Rim appear the dependent inertia being expanded and reinforced once specific paths had been formed at the beginning. Apparently, these institutional and strategic measures would have a positive or negative influence on shaping the maritime networks in East Sea Rim, resting upon the overlapped ones. Even so, when North Korea launch missiles or take a nuclear bombing experiment, the other East Asian countries fall into dilemma to cut off the network or to have a negative effect on the network. The rapid increase of the Chinese migration into the Far Eastern Russia may also have a negative impact on improving the customs procedures there.