Aoyagi Kiyonaga served as a bushō during the Sengoku period.

Kiyonaga was born as the second son of Nishina Morikuni.  Kiyonaga was the lord of Aoyagi Castle in the Tsukama District and a retainer of the Kai-Takeda based in Shinano Province.

The Aoyagi were members of the Omi clan of Shinano.  Kiyonaga was adopted from the Nishina clan and initially affiliated with the Ogasawara clan of Shinano, serving as a retainer of Ogasawara Nagatoki.  Beginning in 1542, Takeda Harunobu (later known as Takeda Shingen) invaded Shinano.  Following a defeat to the invading forces, Kiyonaga entered into service for the Kai-Takeda clan and commanded a battalion of 50 cavalry soldiers.  He became a member of a corps led by Ichijō Nobutatsu his younger brother of a different mother).  In 1553, Harunobu granted Kiyonaga the Omi township.  Thereafter, Kiyonaga adopted the surname of Omi.  His lineal heir, Aoyagi Yorinaga, inherited the headship of the clan but, in 1587, the Omi family fell into ruin.

Kiyonaga died in 1569.  He founded the Kiyonaga Temple in the village of Chikuhoku in the Higashi-Tsukama District of Shinano.