Resident Population in Harrison County, MO was 8.22000 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Harrison County, MO reached a record high of 10.30000 in January of 1971 and a record low of 8.15600 in January of 2020. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Harrison County, MO - last updated from the United States Federal Reserve on May of 2024.