William Barker Cushing (4 November 1842–17 December 1874) was an officer in the United States Navy, best known for sinking the Confederate ironclad CSS Albemarle during a daring nighttime raid on October 27, 1864, a feat for which he received the thanks of Congress.

Cushing was born in Delafield, Wisconsin and was raised in upstate New York. He was expelled from the United States Naval Academy for pranks and poor scholarship. At the outbreak of the American Civil War, however, he pled his case to United States Secretary of the Navy Gideon Welles, was reinstated and went on to acquire a distinguished record, frequently volunteering for the most hazardous missions. His heroism and coolness under fire were legendary. One biographer referred to Cushing as "Lincoln's commando." Cushing was promoted to lieutenant in 1862, and to commander in 1872, although many historians believe he deserved even greater honors. Both of his brothers died in uniform, one in the Battle of Gettysburg in 1863, and another while fighting the Apaches in 1871.

Cushing commanded several U.S. warships after the Civil War, and died leaving a widow and two daughters.

Five ships in the U.S. Navy have been named USS Cushing for him.