Rhee Syngman proposed the plan for Pacific pact, which was intended to secure the Asian collective security system, as an alternative for Korean and Asian security in the clod war. In 1949, for the purpose of forming a powerful military alliance organization such as North Atlantic Treaty Organization(NATO), he tried to organize Pacific pact in association with Quirino in the Philippines and Chiang Kaishek in the Chinese Nationalist Party, but failed to do. In 1953, in order to secure domestic defense and the collective security system, he concluded Mutual Defense Treaty between the Republic of Korea and the United States of America. And then in June 1954, he took the initiative in organizing the Asian People’s AntiCommunist League(APACL) in order to take an opportunity to unite anti-communist nations and form Pacific pact. Meanwhile USA had a plan for the strategy of Asian regional union in which Japan played an important role. American policy which sought to make Japan a base of Asian anti-communism was revealed by an independent economic union between Korea and Japan, and Japan’s economic policy toward Korea aimed at withdrawing Korea’s claim for compensation. Running counter to American policy, Rhee Syngman suggested that Korea could play the part of Asian anti-communist base, and Asian security be preserved by accomplishing the balance of power between Korea and Japan equally. Thus, Pacific pact promoted by Rhee Syngman regime was characterized by firm anti-Japanese feature as well as anti-communism.