Lifespan: Eishō 16 (1519) to Tenshō 13 (1585)
Rank: bushō; sengoku daimyō; lord of Ōzu Castle
Title: Governor of Tōtōmi
Father: Utsunomiya Kiyotsuna
Siblings: Kasama Masatsuna, Hagimori Fusatsuna
Children: Toyouji, daughter (formal wife of Ichijō Kanesada), daughter (wife of Ōno Naoyuki)
Utsunomiya Toyotsuna served as a bushō during the Sengoku and Azuchi-Momoyama periods. Toyotsuna was a sengoku daimyō in Iyo Province. He served as the eighth and last head of the Iyo-Utsunomiya clan and as lord of Ōzu Castle.
Toyotsuna was born in 1519 as the son of Utsunomiya Kiyotsuna. The Iyo-Utsunomiya were a cadet family of the Utsunomiya clan and members of the same family as the Shimotsuke-Utsunomiya. The Iyo-Utsunomiya established their base of power in the Kita District.
In the era of Toyotsuna, the Iyo-Utsunomiya were confined between the Kōno clan (the military governors of Iyo governing the Dōgō area) and the Saionji clan of the Uwa District. In addition, clans based outside of Iyo including the Ichijō of neighboring Tosa Province, the Ōtomo of Bungo Province in northeast Kyūshū, and the Ōuchi and Mōri clans of western Japan all had significant dealings in the province.
In battle against the Saionji clan, Toyotsuna performed valiantly and slayed Saionji Kintaka, the son of Saionji Sanemitsu (the head of the Saionji clan who controlled the southern portions of Iyo). Thereafter, he joined forces with the Ichijō clan after forging a political alliance through the marriage of his daughter to Ichijō Kanesada, a sengoku daimyō. This alliance enabled Toyotsuna to confront the rival Kōno clan. However, in 1568, he incurred a major defeat at the Battle of Tosakatōge against the Kōno bolstered by reinforcements from the Mōri.
In 1585, Toyotsuna died of illness in Bingo Province on Honshū.