Mendon is a town in Worcester County, Massachusetts, United States. The population was 5,839 at the 2010 census.
The Nipmuc people once inhabited Mendon, and Nipmuc Pond is named for them. The early settlement at Mendon was first listed in Essex County in 1667, then in 1671 in Suffolk County, and in Worcester County from 1731. Mendon was first settled in 1660 and was officially incorporated in 1667. The town was originally 64 square miles (170 km2), including the modern-day towns of Milford, Bellingham,Hopedale, Uxbridge, Upton, Blackstone, Northbridge and Millville. For this reason, the town of Mendon is sometimes referred to as "Mother Mendon". Benjamin Albee (1614–1695) erected a water-powered mill on Mill River in 1664 where it crosses modern-day Hartford Avenue. and was one of the town's important early residents. The mill was the first water-powered grist mill in the region.