William Howard Hoople (August 6, 1868 – September 29, 1922) was an American businessman and religious figure. He was a prominent leader of the American Holiness movement; the co-founder of the Association of Pentecostal Churches of America, one of the antecedent groups that merged to create the Church of the Nazarene; rescue mission organizer; an ordained minister in the Church of the Nazarene, and first superintendent of the New York District of the Church of the Nazarene; YMCA worker; baritone gospel singer; successful businessman and investor; and inventor.