Shimanto is a city in southwestern Kōchi Prefecture, Japan. As of 31 July 2022, the city had an estimated population of 32,593 in 16635 house…Shimanto is a city in southwestern Kōchi Prefecture, Japan. As of 31 July 2022, the city had an estimated population of 32,593 in 16635 households, and a population density of 52 persons per km². The total area of the city is 632.29 square kilometres.