In 764, Oguromaro was invested as Jugoinoge (Junior Fifth Rank, Lower Grade) and a director of Ise Province by a determination of rewards according to each person's merits (after examining his services) at the time of Rebellion of FUJIWARA no Nakamaro.
天平宝字8年（764年）藤原仲麻呂の乱の際の論功によって従五位下・伊勢国守に叙せられる。