Tsukumi is a city located in Ōita Prefecture, Japan. The city was founded on April 1, 1951.As of March 31, 2017, the city has an estimated population of 18,341, with 8,384 households and a population density of 230 persons per km². The total area is 79.48 km².Notable people from TsukumiYasuei Yakushiji, former professional boxer