The Ōkubo clan (Japanese: 大久保氏, Hepburn: Ōkubo-shi) were a samurai kin group which rose to prominence in the Sengoku period and the Edo periods.

[2] The Ōkubo clan traces its origins to 16th century Mikawa Province.

[2] The Ōkubo claimed descent from the Utsunomiya clan, descendants of Fujiwara no Michikane (955–995).

Both brothers were among the seven closest retainers of Matsudaira Hirotada, the father of Tokugawa Ieyasu.

The head of this clan, Ōkubo Tadanori line was ennobled as a viscount ("shishaku") in the kazoku peerage system.