Highland Mills is a hamlet in Orange County, New York, United States. The population was 3,468 at the 2000 census, at which time it was a census-designated place. It is part of the Poughkeepsie–Newburgh–Middletown, NY Metropolitan Statistical Area as well as the larger New York–Newark–Bridgeport, NY-NJ-CT-PA Combined Statistical Area.Highland Mills is in the Town of Woodbury adjacent to the New York State Thruway.