New Marlborough is a town in Berkshire County, Massachusetts, United States. It is part of the Pittsfield, Massachusetts Metropolitan Statistical Area. The population was 1,528 at the 2020 census. New Marlborough consists of five villages: Clayton, Hartsville, Mill River, New Marlborough Village and Southfield.

Berkshire County is the westernmost county in the U.S. state of Massachusetts. As of the 2020 census, the population was 129,026. Its largest city and traditional county seat is Pittsfield. The county was founded in 1761. The Berkshire Hills are centered on Berkshire County. Residents are known as Berkshirites. It exists today only as a historical geographic region, and has no county government, with the exception of the retirement board for former county workers, and certain offices such as the sheriff and registry of deeds.