Marlboro is a hamlet (and census-designated place) in Ulster County, New York, United States. The population was 2,339 at the 2000 census.
Marlboro is in the southeast part of the Town of Marlborough and also the southeast corner of Ulster County.
The community was the site of the first settlement in the town, around 1697. Marlboro also houses the Gomez Mill House. The Gomez Mill House is now a Historical Site. It is the oldest Jewish residence in Ulster County. It was the first paper mill in Ulster County. Marlboro is also the hometown of Jersey Shore star, Snooki.