Massillon is a city in western Stark County, Ohio, United States, along the Tuscarawas River. The population was 32,146 at the 2020 census. M…Massillon is a city in western Stark County, Ohio, United States, along the Tuscarawas River. The population was 32,146 at the 2020 census. Massillon is a principal city of the Canton–Massillon metropolitan area, which includes all of Stark and Carroll counties and had a population of 401,574 in 2020.