Nagamori Castle (長森城, Nagamori-jō) was a castle built in Mino Province, Japan, by Tosanobō Shōshun (土佐坊昌俊), in 1185, and lasted from the Heian period to the early Sengoku period.

After the castle was dismantled in the beginning of the Sengoku period, the Kiridōshi Jin'ya was built on the same spot.

It served as the base for the area shugo until the construction of Kawate Castle nearby.

During the Nanboku-chō period, Toki Yoritō served as the shugo of Mino Province.

The castle only remained in the hands of the Toki clan for a short time, however, as Toki Yoriyasu built the more spacious Kawate Castle nearby to serve as the new base of operations.