The naval Battle of Hakodate was fought from 4 to 10 May 1869, at the beginning of the Meiji Restoration, near the northern Japanese island of Hokkaido, between the remnants of the Shogun's navy, consolidated into the armed forces of the rebel Ezo Republic, and the newly formed Imperial Japanese Navy.

The naval forces of the Ezo Republic were grouped around the warship Kaiten . The fleet originally consisted of eight steamships: Kaiten , Banryo , Chiyodagata , Chogei, Kaiyō Maru, Kanrin Maru, Mikaho and Shinsoku. However Kaiyō Maru had been lost in a previous engagement in front of Esashi, and Kanrin Maru had been captured by Imperial forces after suffering damage in bad weather.

For the operation, an Imperial Japanese Navy fleet had been rapidly constituted around the French-built ironclad Kotetsu, which had been purchased from the United States. Other Imperial ships were Haruhi , Hiryu , Teibo and Yoharu .

The Imperial fleet supported the deployment of troops on the island of Hokkaido, destroyed onshore fortifications and attacked the rebel ships. On May 4th, Chiyodagata was captured by Imperial forces after having been abandoned in a grounding, and on the 7th, Kaiten was heavily hit and put out of action. The rebel's Banryo managed to sink the Imperial forces' Choyo , but she later sank in turn because of heavy damage.

The Imperial Japanese Navy won the engagement, ultimately leading to the surrender of the Shogun forces at the end of May 1869.

Ships of foreign navies — HMS Pearl of the British Navy, and the French Navy's Coetlogon — were standing by neutrally during the conflict. The French captain Jules Brunet who had trained the rebels and helped organize their defenses, surrendered on Coetlogon on June 8 1869.

The future Admiral of the fleet Heihachiro Togo participated in the battle on the Imperial side as a young third-class officer, onboard Haruhi.