Ōbu is a city located in Aichi Prefecture, Japan. As of 1 October 2019, the city had an estimated population of 92,179 in 39,382 households, and a population density of 2,739 persons per km2. The total area of the city is 33.66 square kilometres (13.00 sq mi). Ōbu has been a member of the World Health Organization’s Alliance for Healthy Cities (AFHC) since June 5, 2000.

Aichi Prefecture is a prefecture of Japan located in the Chūbu region of Honshū. Aichi Prefecture has a population of 7,552,873 and a geographic area of 5,172.92 square kilometres (1,997.28 sq mi) with a population density of 1,460 inhabitants per square kilometre (3,800/sq mi). Aichi Prefecture borders Mie Prefecture to the west, Gifu Prefecture and Nagano Prefecture to the north, and Shizuoka Prefecture to the east. Nagoya is the capital and largest city of the prefecture.