Oichi (お市; 1547 – June 14, 1583) was a female historical figure in the late Sengoku period. She is known primarily as the mother of three daughters who became prominent figures in their own right – Yodo-dono, Ohatsu and Oeyo. Oichi was the younger sister of Oda Nobunaga; and she was the sister-in-law of Nōhime, the daughter of Saitō Dōsan. She was descended from the Taira and Fujiwara clans.
She was an influential figure in Japanese history in the Sengoku period. Although remembered mainly for her tragic life as sister of Oda Nobunaga, Japan's first unifier since Ōnin War, Oichi is also famous for her honorable conduct, her beauty and determination. She was present at two historically significant battles, the siege of Odani and the siege of Kitanosho, sieges that led to the extermination of the powerful Azai and Shibata clan, respectively.