The purpose of this article is to reveal the fact that Durham W. Stevens controlled Korean diplomacy under the supervision of Komura Jutaro, Japanese Ministry of Foreign Affairs, and Hayashi Gonsuke, Japanese Minister to Korea, during the period of Japan’s seizure of Dokdo in February 1905 by looking into the responses made by Japan and foreign countries to the appointment of Stevens to diplomatic adviser to Korean Department of Foreign Affairs and his activities. Japanese press welcomed Korea-Japan Agreement of August 1904 since it would enabl e Japan to control Korean foreign affairs by allowing Japanese Ministry of Foreign Affairs to supervise Korean diplomacy through Stevens. Though some journals expressed concerns about the limit of sanction sin case of discord between Stevens and Japanese government, they did not fully catch the intentions of Japanese government concealed in the articles of the Agreement. The diplomats and journals in major powers such as the United States, Great Britain and Russia recognized that Korea fell to a Japanese colony by Japan’s control of Korean diplomacy. They thought that Stevens could not help being ordered by Japanese government. It is worth mentioning that Stevens asked Horace N. Allen, American Consul General to Korea, to make his contract not publicized. Stevens kept his position as the employee of Japanese Ministry of Foreign Affairs Assigned to the Japanese Legation in Washington D.C. after taking the position of diplomatic adviser to Korean Department of Foreign Affairs. He controlled Korean diplomacy tightly. When he noticed that Emperor Kojong would send as overeign’s message to foreign powers denouncing the injustice of Japan’s dominion over Korea, he made every effort to stop it. After a discussion with Hayashi, he pressed Emperor Kojong menacingly in his audience with the emperor. This means that Stevens and Hayashi tightly watched Emperor Kojong and those around him with all available means. Stevens had an audience with Emperor Kojong again when he obtained the information that Emperor had Jo Min-Hee, Korean Minister in Japan, deliver a secret message to Charles W. Needham, who was President of Columbia University and the Adviser to Korean Consulate in the United States. Stevens had the information from the Japanese Legation in the United States and made a strong protest to the emperor, urging him to conduct foreign affairs after getting his advise as stipulated in the contract. Stevens was in complete control of Korean diplomacy under the order and supervision of Japanese government in those days when Japan usurped Dokdo. Thus it was impossible for Korean government to have an accurate grasp of the seizure of Dokdo, which proceeded in secret, and to make a protest against it. Therefore the Japanese argument that, since Japan began to supervise Korean foreign affairs only with Japan’s Usurpation of Korea’s Foreign Affair Protectorate, Korea could have made protest against the seizure of Dokdo if Korea had historical and administrative claim on the island is a direct lie and sophistry.