Oak Beach is a small community and census-designated place located near the eastern end of Jones Beach Island, a barrier island between the Atlantic Ocean and the Great South Bay of Long Island. The community is part of the village of Babylon in Suffolk County, New York, United States. The eastern part, the Oak Island Beach Association, is gated, whereas the western part is not. The Oak Beach CDP was first listed prior to the 2020 census. Prior to that the community was part of the Oak Beach–Captree census-designated place.

The Town of Babylon is one of ten towns in Suffolk County, New York, United States. Its population was 218,223 as of the 2020 census. Parts of Jones Beach Island, Captree Island and Fire Island are in the southernmost part of the town. It borders Nassau County to the west and the Atlantic Ocean to the south. At its westernmost point, it is about 20 miles (32 km) from New York City at the Queens border, and about 30 miles (48 km) from Manhattan. The village of Babylon is also within the town.