Sound Beach, established in 1929, is a hamlet and census-designated place (CDP) in the north part of the Town of Brookhaven in Suffolk County, New York, United States.

[3] It is bordered on the north by Long Island Sound, by Rocky Point to the east, and Miller Place to the west.

According to the United States Census Bureau, the CDP has a total area of 1.6 square miles (4.2 km2), all land.

The local volunteer fire department sits near the square on Sound Beach Boulevard.

The beaches along the coast of Long Island Sound are constantly endangered by harsh winter storms.

The terrain of the beaches is sandy on and near the cliffs and gradually becomes rockier along the immediate shoreline.