The three prominent leaders in the Korean society in America were Yongman Park, Changho Ahn, Syngman Rhee. As of 1932 with the turning point, they disappeared ore were less influential on the Koreans in America. New types of leaders emerged in Hawaii and the mainland in the mid 1930s. They were different from the three leaders. They earned their living, carrying out the independence movement at the same time. Just before the outbreak of Pacific War, Koreans in Hawaii and mainland succeeded in： forming United Korean Committee(UKC). They started independence movement against Japanese Imperialist. The main activities of UKC were divided into three parts : support the Korean Provisional Government(KOPOGO); diplomatic and propaganda activities for the cause of Korean independence; and aid the national defense activities of United States. Syngman Rhee took part of the diplomatic mission of UKC, so he formed the Korean Commission. Rhee demanded US recognition of the KOPOGO and military aid to the Korean independence movement. Although the diplomatic approach was not successful, the approach to the military authority and the proposal for the establishment of the Korean guerrilla unit was accepted by the United States to a certain extent. Rhee came into close relations with officials in military intelligence agency and made them his private lobbyist. Kilsoo Haan was the political rival of Rhee during the Pacific War. He was spotlight by the mass media after the Pear Harbor, because he predicted the Japanese attack. He was a white lier for the cause of Korean independence but his conflict with Syngman Rliee and KOPOGO endangered the unity of UKC. UKC was spilt into two parts after the clash between Syngman Rhee and Kukminhur. KOPOGO strongly supported the Syngman Rhee side. Also there was the ideological contradiction between political activists for the independence movement. The revolutionary group were formed and the argument between the conservative group and revolutionary one started. In 1945, the Office of Strategic Service(OSS) prepared special project on the penetration into Japanese territory, named Napko project. It was planned by the special agents who has experienced the detachment 101 in Burma. If it were not for the volunteer Korean agents, Napko project could not be started. At least 19 Koreans in the United States took part in Napko project. Three categories of Koreans joined OSS : thoese who served in US Army or OSS; those who were civilian residents in US; those who were the prisoner of war. They were all volunteers who staked their lives on the battle against Japan. The trained in Santa Catalina island for several months. However, Japan was defeated before they deployed into target point. During the Pacific War, the Koreans in America provided financial and material assistance for anti-Japanese movement. They did their best for the liberation of their mother's land. They sincerely performed as Korean in terms of morale.