Shark Key is an island in the lower Florida Keys about 7 miles (11 km) east of Key West.

It is located north of, and connected to, U.S. 1 (or the Overseas Highway) at approximately mile marker 11.5, between the Saddlebunch Keys and Big Coppitt Key. It is part of the census-designated place of Big Coppitt Key, Florida.

Its earlier name was Stark Key.