The 32-year-old Fort Lauderdale man was in the waters off Nippers Beach on Guana Cay when he was attacked around 5:30 p.m., the Royal Bahamas Police Force said.
The man, whose name was not released, was airlifted to a hospital for treatment, police said.
His condition was not immediately clear.
This comes one week after an American woman was killed by sharks while snorkeling with her family in the Bahamas.
Jordan Lindsey, a 21-year-old college student from California, was swimming in waters near Rose Island when she was attacked, police said.