The Battle of Koshu-Katsunuma was a battle of the Boshin War that was fought in south-central Honshu on 29 March 1868.
Following the Battle of Toba-Fushimi, the pro-Imperial forces of the Choshu, Satsuma, and Tosa Domains split into three columns, which progressed northeast towards the Tokugawa capital of Edo up each of three three main highways: Tokaido, Nakasendo, and Hokurikudo. At the same time, Shinsengumi leader Kondo Isami withdrew to Edo, where he met with the Shogunal general Katsu Kaishu and created the Koyo Chinbutai from the surviving remnants of the Shinsengumi. This corps departed Edo on 24 March, while the Imperial army occupied the Tokugawa stronghold of Kofu and confronted the Shogunal forces at Katsunuma on 29 March. The Shogunal forces, outnumbered ten to one, were defeated with 179 casualties, and Kondo and the other survivors fled to the Aizu Domain via Sagami Province, which was still controlled by Tokugawa hatamoto loyalists. Isami was captured soon after the battle and beheaded, demoralizing the Tokugawa supporters and contributing to the surrender of Edo Castle without bloodshed later that year.