USS Mertz (DD-691) was a World War II-era Fletcher-class destroyer in the service of the United States Navy, named after Rear Admiral Albert Mertz. Mertz was laid down by Bath Iron Works Corp., Bath, Maine, 10 May 1943; launched 11 September 1943; sponsored by Mrs. Selma M. Allen, daughter of Rear Admiral Mertz; and commissioned at Charlestown, Massachusetts, 19 November 1943, Commander William S. Estabrook, Jr., in command.