Sheepshead Bay is a bay separating the mainland of Brooklyn, New York City from the eastern portion of Coney Island, the latter originally a barrier island but now effectively an extension of the mainland with peninsulas both east (the neighborhood of Manhattan Beach) and west (the neighborhood of Sea Gate). Its mouth is about a mile (1.6 km) southwest of Marine Park, Brooklyn. The area is part of Brooklyn Community Board 15.

The bay itself was originally the easterly entrance to Coney Island Creek but filling of the central part of this waterway during the 1930s in conjunction with construction of the Shore Parkway portion of the Belt Parkway eliminated access to the creek. At the same time the bay was widened at its western end, deepened and bulkheaded. It is now the home of recreational fishing fleets. The fishing fleet has been shrinking every year and being replaced by dinner boats. At the Western end of the bay, there is a Holocaust memorial park, which is used throughout the year for commemorative events.

In the last decade of the 20th century, a real estate boom brought the reopening of the landmark Lundy Brothers seafood restaurant, which closed again in 2007, as well as the opening of Soviet-style restaurants/nightclubs such as Paradise and Baku Palace. The waterfront also experienced a growth of condominium developments. Emmons Avenue, the northern shoreline street along the bay, has piers with an active seafood market and tour boats.

Sheepshead Bay is named for the sheepshead, an edible fish once found in the bay's waters.

As of 2007, there were 123,181 people living in Sheepshead Bay. The demographics were 75.4% White, 14.6% Asian, 6.6% Hispanic or Latino, 4.7% African American and 0.2% Native American. Many are Russian. There are a lot of Catholics as well.

Subway service to Sheepshead Bay is provided by the BMT Brighton Line (B and Q trains), with local stops at Avenue U and Neck Road, and express-local stops at the Kings Highway and Sheepshead Bay Road station. The main shopping and business thoroughfares are Emmons Avenue, Sheepshead Bay Road, Ocean Avenue, and Nostrand Avenue. Emmons Avenue is at the west end of the shore Greenway which lies between Shore Parkway and Jamaica Bay, connecting eastward and northward to Canarsie and Cross Bay Boulevard. Emmons Avenue is a waterfront road with piers from which yachts and boats offer day trips for fishing and dancing.

Several public schools serve the community: Sheepshead Bay High School; JHS 14 Shell Bank Intermediate School; The Bay Academy; P.S. 254 and P.S. 52 (elementary). Private schools in the area include the St. Mark's School and St. Edmund's. Kingsborough Community College, part of the City University of New York (CUNY) is nearby. Sheepshead Bay is patrolled by the NYPD's 61st Precinct.

Much like its neighobor, Brighton Beach, Sheepshead Bay is known for its high concentration of immigrants from the former Soviet Union. Many stores and buildings are bilingual with both English and Russian signage. Other ethnic groups include Italians, Irish, Jews, Turkish, Chinese and some Spanish.

Sheepshead Bay is served by the independent news blog Sheepshead Bites.

Notable current and former residents of Sheepshead Bay include:

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