Kiyosu is a city in Aichi Prefecture, Japan. As of 1 October 2019, the city had an estimated population of 69,687 in 29,477 households, and a p…Kiyosu is a city in Aichi Prefecture, Japan. As of 1 October 2019, the city had an estimated population of 69,687 in 29,477 households, and a population density of 4,017 persons per km². The total area of the city is 17.35 square kilometres.