The suspension of the Korea-Japan conference was a burdensome incident to both countries. The Japanese Diet`s internal record on Dokdo is an important source that shows Japan`s responsive policies to Korea at that time. During the process of the Korea-Japan conference, oral arguments over the right of claim led to suspension of the conference. It took four years and six months to restsart the Korea-Japan conference, and during the suspension, The Japanese Diet discussed a variety of policies regarding the Korean peace line and Dokdo issue. There were strong voices claiming that Korea`s peace line issue should be solved by military power, and the Dokdo issue by the ICJ. The Korea-Japan conference suspension, however, was not the problem of only Korea and Japan, but also the problem of the U.S. which had deep interest relations in East Asian security issues within the Cold War system. Thus, the Japanese Diet`s policies toward Korea do not progress as planned, and the decreased importance of the Japanese Department of Foreign Affairs due to the discontinuity of Korea-Japan conference is on cause of this poor progress. As communication between Korea and Japan becomes difficult due to the cease of the conference, the Japanese Diet claims that Japan take the Dokdo issue to the ICJ and form a stronger claim over Dokdo sovereignty. This research paper is constituted of the following four chapters. The first chapter explains this research`s difference from previous ones and this research`s contribution to the academic field. The second chapter analyzed the Korea-Japan conference suspension and the Japanese Diet`s response, and the third chapter analyzes the Korean lighthouse establishment in Dokdo and the Japanese Diet`s response and limits. Finally, the fourth concluding chapter analyzes why Dokdo is Korea`s territory, and the limits of Korean Dokdo policies according to the Japanese Diet.