Ōta (大田区, Ōta-ku^?) is one of the 23 Special wards of Tokyo, Japan. As of May 1, 2011, the ward has an estimated population of 676,458, with 348,492 households, and a population density of 11,376.69 persons per km². The total area is 59.46 km², the largest of the 23 special wards.

Ōta's hub is situated around the two Kamata Stations (JR Kamata and Keikyu Kamata) where the Ōta Ward Office and central Post Office can be found.