Nanbu Toshinao

was an early Edo period Japanese samurai, and the 1st daimyō of Morioka Domain in northern Japan. He was the 27th hereditary chieftain of the Nanbu clan.

Toshinao was the eldest son of Nanbu Nobunao, and was born at the clan's Tago Castle in Sannohe. In 1590, Nobunao submitted to Toyotomi Hideyoshi during the SIege of Odawara and was confirmed as daimyō of his existing holdings in northern Mutsu province (the districts of Nukanobu, Hei, Kazuno, Kuji, Iwate, Shiwa and Tōno). During the same year Maeda Toshiie, one of Hideyoshi's closest generals, presided over Toshinao's genpuku ceremony, and granted him the kanji of "Toshi" in his name. In 1594, he married the daughter of Gamō Ujisato. In 1626 he was elevated to Junior Fifth Rank, Lower Grade.

He died at the clan's Sakuradaya residence in Edo in 1632 at the age of 57, and was succeeded by his son, Nanbu Shigenao. His grave was originally at the temple of Shōju-ji in Sannohe, but was later relocated to the Nanbu clan mortuary temple of Tōzen-ji in Morioka.