Matsudo is a city in Chiba Prefecture, Japan. As of 30 November 2020, the city had an estimated population of 498,575 in 242,981 households and a population density of 8100 persons per km². …Matsudo is a city in Chiba Prefecture, Japan. As of 30 November 2020, the city had an estimated population of 498,575 in 242,981 households and a population density of 8100 persons per km². The total area of the city is 61.38 square kilometres.