The Trial of Cooperation of the Asia-Pacific Region: The Exchange of the Goodwill Mission between Japan and Australia Kazuomi SAKAI In 1934, J.G. Latham, a deputy prime minister of Australia, visited Japan. Debuchi Katsuji, Japanese former Ambassador to the United States, went to Australia for return in the next year. The purpose of this paper is to explore why Japan and Australia exchanged goodwill at the time when the order of the Asia-Pacific region had collapsed quickly. Japan aimed at solution of the uneasiness about the security which Australia has held, and the trade deficit to Australia. Australia aimed at establishing the new foreign policy to the Asia-Pacific region where the importance was increasing. Both Japan and Australia are trying to be concerned with new order formation of the Asia-Pacific region. Japan is trying to include Australia in the Asia-Pacific order centering on Japan. On the other hand, Australia tended to promote economic relation with the Asia-Pacific region as a member of the Commonwealth in British Empire, with white Australia policy maintained. Japan-Australia goodwill exchange ended in failure because the gap between them about the Asia-Pacific order was not filled. However, this exchange of goodwill mission had became the requisite into which Japan and Australia convert the Asia-Pacific policy after World War II.