Hugh Clowers Thompson, Jr. (April 15, 1943 – January 6, 2006) was a United States Army warrant officer in 123rd Aviation Battalion, 23rd Infantry Division, who played a major role in ending the My Lai Massacre in Sơn Mỹ Village, Sơn Tịnh District, Quang Ngai Province, South Vietnam, on March 16, 1968.