The Town of Hempstead is one of the three towns in Nassau County in the U.S. state of New York. It occupies the southwestern part of the county, on the western half of Long Island. Twenty-two incorporated villages are completely or partially within the town. The town's combined population was 759,757 at the 2010 census, which is the majority of the population of the county and by far the largest of any town in New York. In 2019, its combined population increased to an estimated 759,793 according to the American Community Survey.
If Hempstead were to be incorporated as a city, it would be the second-largest city in New York, behind New York City; it is more than three times the size of Buffalo, which has long been the state's second-largest city. It would be the 18th-largest city in the country, behind Indianapolis, Indiana and ahead of Seattle, Washington. Hempstead is thus the most populous municipality in the New York metropolitan area outside New York City.
Hofstra University's main campus is located in Hempstead.