Midori-ku is one of ten wards of the city of Saitama, in Saitama Prefecture, Japan, and is located in the southeastern part of the city. As of 1 March 2021, the ward had an estimated population of 129,705 and a population density of 4,900 persons per km2. Its total area was 26.44 square kilometres (10.21 sq mi).

Saitama is the capital and largest city of Saitama Prefecture, Japan. Its area incorporates the former cities of Urawa, Ōmiya, Yono and Iwatsuki. It is a city designated by government ordinance. As of 1 February 2021, the city had an estimated population of 1,324,854, and a population density of 6,093 people per km². Its total area is 217.43 square kilometres (83.95 sq mi).