Nanbu Nobuoki (南部信恩, 6 November 1678 – 31 December 1707) was a mid-Edo period Japanese samurai, and the 5th daimyō of Morioka Domain in northern Japan.

[1] Nobuoki was the 3rd son of Nanbu Yukinobu, the 4th daimyō of Morioka Domain.

As his older brother died young, he became heir on 1 May 1701, and was received in formal audience by shōgun Tokugawa Yoshimune on 15 May.

On 25 July, he wed the daughter of Mōri Tsunamoto, daimyō of Chōfu Domain and on 18 December received the formal courtesy title of Bingo-no-kami.

During his short tenure, he was unable to overturn the strong influence of Confucianism introduced by his father into the domain's administration, and died on 31 December 1707 at a relatively young age.