Millbrook is a village in Dutchess County, New York, United States. Millbrook is located in the Hudson Valley, on the east side of the Hudson River, 90 miles north of New York City. Millbrook is near the center of the Town of Washington. As of the 2010 Census, Millbrook's population was 1,452. It is often referred to as a low-key version of the Hamptons and is one of the most affluent towns in New York State.Millbrook is part of the Poughkeepsie–Newburgh–Middletown Metropolitan Statistical Area as well as the larger New York–Newark–Bridgeport Combined Statistical Area.