Stony Brook is a hamlet and census-designated place (CDP) in the Town of Brookhaven in Suffolk County, New York, United States, on the North Shore of Long Island. Begun in the colonial era as an agricultural enclave, the hamlet experienced growth first as a resort town and then to its current state as one of Long Island's major tourist towns and centers of education. Despite being referred to as a village by residents and tourists alike, Stony Brook has never been legally incorporated by the state. The population was 13,740 at the 2010 census.

Brookhaven, formally the Town of Brookhaven, is a large suburban town in Suffolk County, Long Island, New York. With a population of 488,497 as of 2022, it is the second most populous town in the United States and in New York and the third most populous community in the state.