Utsu Tadashige served as a bushō during the Sengoku period.  He was a retainer of the Matsudaira clan of Mikawa Province and the founder of the Ōkubo clan.

In 1476, Tadashige was born as the son of Utsu Tadatomo, a retainer of the Matsudaira clan.

In 1526, when Matsudaira Kiyoyasu planned to launch a surprise attack against Matsudaira Masayasu in a bid to capture Okazaki Castle, Tadashige warned against the plan and, instead, recommended that he first capture Yamanaka Castle (an outlying base) and then urge Masayasu to surrender.  Owing to the success of this course of action, Kiyoyasu promised to provide Tadashige with any reward desired for his exemplary contributions, but Tadashige firmly refused and only obtained permission to open a market in his territory.  At this market, Tadashige showed empathy toward impoverished residents by reducing taxes for which the residents called Kiyoyasu a virtuous lord.  Kiyoyasu then praised Tadashige for his loyalty.