Nishio clan (西尾氏, Nishio-shi) was a Japanese samurai kin group.

Kira Yoshitsugu, a son of Kira Mochihiro, served under Oda Nobunaga, Toyotomi Hideyoshi and Tokugawa Ieyasu adopted the family name of Nishio.

[2] Nishio Yoshitsugu was given the 12,000 koku Haraichi Domain in Musashi Province in 1602.

His son, Nishio Tadanaga was transferred to the 20,000 koku Shirai Domain in Kōzuke Province in 1616, and subsequently to Tsuchiura Domain (Hitachi Province) from 1617-1649.

After the Meiji Restoration, the Nishio clan was transferred to the short-lived Hanabusa Domain in Awa Province, and was subsequently granted the kazoku title of viscount (shishaku).