Walter Cleveland Cowles (July 11, 1853 – November 27, 1917) was an admiral in the United States Navy.

Naval Academy at the age of sixteen, graduating in 1873.

As captain of the battleship USS Kentucky, he sailed around the world with the Great White Fleet in 1908–1909.

In March 1915, Cowles became one of the first full admirals in the history of the U.S. Navy when the three commanders in chief of the Atlantic, Pacific, and Asiatic Fleets were all advanced to the temporary rank of full admiral while so serving.

Upon relinquishing command of the Asiatic Fleet in June 1915, Cowles reverted to his permanent rank of rear admiral.