Abstract: After the World War II, Japan suffered huge changing at many aspects, including politics, economics and social structure. As a part of political system, Japanese diplomacy also changed a lot. Before the WWⅡ, the Tenno had never been out of Japan and taken part in the diplomatic activities. However, after Tenno Showa’s visiting USA, the “Tenno’s Diplomacy” became a vital link and began to play an important role in the postwar diplomacy system in Japan, which improved the allround exchange and connection between Japan and other nations in the fields of politics, government, economics and civil communication, and shaped a stable normal form gradually. We should be alert to the “Tenno’s Diplomacy” during the postwar period as it was disguised strongly.

Key words: post-war Japan, Tenno’s diplomacy, visiting USA, normal form of diplomacy