Ian Hennessy (born 10 January 1967) is an Irish soccer coach and former professional player who was most recently the head coach of the University of Delaware. He came to the United States after being rejected by Arsenal, then returned to Ireland, playing for Cork City in their inaugural season in the League of Ireland during 1984. He also played for the Ireland youth team. Hennessy holds a PhD in Molecular Biology from Columbia University in New York City and a bachelor's degree from Seton Hall.