Resident Population in Martin County, FL was 165.66600 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Martin County, FL reached a record high of 165.66600 in January of 2024 and a record low of 28.03500 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Martin County, FL - last updated from the United States Federal Reserve on September of 2025.