John Freeman Mackie (October 1, 1835–June 18, 1910) was a United States Marine Corps sergeant during the American Civil War. He was awarded the nation's highest military decoration for valor—the Medal of Honor, for his actions aboard the USS Galena during the battle with Confederate Marines and artillery batteries at Fort Darling near Richmond, Virginia, on May 15, 1862. He is one of the first two Marines to be awarded the Medal of Honor, and is considered to be the first Marine to receive the Medal of Honor in the history of the Marine Corps.