Beltsville is a census-designated place (CDP) in northern Prince George's County, Maryland, United States. The population was 15,691 at the 2000 census. Geography Beltsville is located at (39.037509, -76.917847), adjacent to the Montgomery County-Prince George's County line. According to the United States Census Bureau, Beltsville has a total area of 6.6 square miles (17.2 km²), all of it land. Demographics As of the census of 2000, there were 15,690 people, 5,690 households, and 3,823 f… (More on Beltsville)