Sumida (墨田区, Sumida-ku, "Field of Ink") is a special ward located in Tokyo Metropolis, Japan. It calls itself Sumida City in English. As of March 1, 2012, the ward has an estimated population of 240,733, with 126,974 households and a population density of 17,507.85 persons per km². The total area is 13.75 km².
Sumida is in the northeastern part of the mainland portion of Tokyo. The Sumida and Arakawa are the major rivers, and form parts of its boundaries. Its neighbors are all special wards: Adachi to the north; Arakawa to the northwest; Katsushika to the east; Edogawa to the southeast; Taitō to the west; Chūō to the southwest; and Kōtō to the south. The ward was founded on March 15, 1947. It was previously the (ordinary) wards Honjo and Mukojima. Mukojima, formed in 1932, contained the former town of Sumida, which along with the river gave the ward its name.