Abstract: After the postwar Japans maritime thought experienced a change from “recognizing the attributes of marine resources” to “recognizing peoples various marine activity systems”, it changed again in the 1990s. Starting with the “Ocean Civilization” initiated by Japanese scholars, relying on the “Marine National Seminar” activities organized by the government think tank and their policy proposals, and legally protected by the states “Ocean Basic Law” and “Basic Plan on Ocean Policy”, the thought ultimately rose to become“New Ocean National Strategy”. This process showed the characteristics of hierarchical ascending. At the same time, Japan has taken a step advancing to the road of being a subordinate or subsidiary “Sea Empire” that is backed by the JapanUS alliance.

Key words: Marine Civilization Theory, Ocean State, New Ocean Strategy, Sea Empire