Mita Tsunahide served as a bushō during the Sengoku period. He served as the lord of Katsunuma and Karakai castles in Musashi Province. He was the son of Mita Masasada and may have been the same individual as Mita Tsunasada.
The Mita clan descended from Taira no Masakado, a member of a gōzoku, or wealthy family, in the Kantō in the tenth century during the Heian period. In the Muromachi period, the Mita clan served the Yamanouchi-Uesugi clan – the deputy shōgun of the Kantō. In the Sengoku period, as the power of the Yamanouchi-Uesugi waned, the Mita came under the command of the Gohōjō clan who were on the ascent. In a record of landholdings of the Odawara group prepared by the Gohōjō in 1559, the Mita are listed among clans from other provinces.
In 1560, after Nagao Kagetora (later Uesugi Kenshin) deployed with a large army to the Kantō in support of Uesugi Norimasa, Tsunahide followed and is identified in records of bushō serving the Uesugi clan at the time of their Kantō expedition. In 1561, Tsunahide also participated in the Siege of Odawara Castle.
After Kagetora returned to his home base in Echigo Province, many of the bushō in the Kantō who obeyed him at the time of the expedition reverted to the command of the Gohōjō clan. Nevertheless, Tsunahide continued to firmly resist the Gohōjō.
Tsunahide moved from Katsunuma Castle, which was not suitable for defensive purposes, to the stronghold of Karakai Castle, but, in 1563, Hōjō Ujiteru toppled this castle. There are also theories that this occurred sooner, either in 1561 or 1562. In any event, Tsunahide fled for protection under Ōta Sukemasa at Iwatsuki Castle in the Saitama District of Musashi, and subsequently took his own life. Tsunahide was seventy-three years old.
His lineal heir, Jūgorō, and second son, Kizō, were entrusted to his retainers but Jūgorō died in 1563 followed by Kizō in 1564. There may have been another son named Gorōtarō, but he killed himself in Izu in 1572.