Pearisburg is a town in Giles County, Virginia, United States. The population was 2,729 at the 2000 census. It is the county seat of Giles County. Pearisburg is part of the Blacksburg Christiansburg Radford Metropolitan Statistical Area. According to the United States Census Bureau, the town has a total area of 3.1 square miles (7.9 Square Kilometer), all of it land.