The main issue of Korea-Japan treaty of 1876 was the Japan’s permanent envoy mission to Seoul and opening two ports, which eventually became to happen during Hanabusa Yoshimoto’s term of office. Wonsan Port was opened during his period of service as Chargé d’affaires and Acting Minister. During Hanabusa’s term as Minister Resident, the Japanese diplomat was permitted to reside in Seoul and Incheon Port was opened. Opening Wonsan Port was executed without tension since both countries shared common interest against Russia’s expansion. However, demanding to authorize the Japan’s permanent envoy mission to Seoul and to open Incheon Port had a strategic intention to strengthen Japan’s political influence over Joseon, which was germane to Hanabusa’s policy. Enomoto Takeaki, the Japanese Minister to Russia who realized the strategic value of Joseon, recommended Hanabusa as the Minister Resident to Joseon when Japan was negotiating over the treaty at Ganghwa island. In June 1876, as nominee for the Minister Resident to Joseon, Hanabusa stated his ‘Joseon policy’ at Saint Petersburg, which was approximately his service plan. In view of Hanabusa’s strategy, political relations and national security was the most important factor than trade. The reason he insisted to open Incheon Port, which is the closest to Seoul, was to strengthen Japan’s political influence over Joseon. Since Hanabusa persistently demanded to open Incheon Port, Joseon government had to concede and suggested Namyang as an alternative. This suggestion was also reflected in the revised instruction (October, 1880). Although Hanabusa constantly persisted Incheon Port even during the negotiation with Kim Hong-chip. As Joseon government bitterly opposed to open Incheon Port by reason of public agitation, Hanabusa used the good cop, bad cop method against Joseon government in the name of protection to accomplish their purpose. Since Japan enforced to open Incheon Port against public criticism, It became one of the primary reasons of Anti-Japanese revolt of 1882(Imogullan). Japanese government made an significant attempt to change the open port from Incheon to Masanpo in Namyang, as Joseon government formerly suggested, after the Im-O Military Revolt in 1882. Nevertheless, it only emphasized the fact that the Japanese government unilaterally pushed to open Incheon Port. Therefore Hanabusa’s policy against Joseon has no choice but to confront the critical assessment.