McGillicuddy or McGillycuddy is a surname of English origin. Notable people with the surname include:
Connie Mack (Cornelius McGillicuddy, Sr., 1862–1956), American professional baseball player, manager, and team owner
Simon Mack(Simon McGillycuddy)
Aided Oliver Cromwell in the plantation of Ireland.
Connie Mack IV (Cornelius Harvey McGillicuddy IV, born 1967), U.S. Representative for Florida's 14th congressional district
Daniel J. McGillicuddy (1859–1936), United States Representative from Maine
John McGillicuddy (1930–2009), American banking industry executive
Valentine McGillycuddy (1849–1939) American surgeon who also served as an Indian Agent
Fictional characters:
Dr. Aloysius McGillicuddy, putative inventor of Fireball Cinnamon Whisky
Lucy McGillicuddy Ricardo, fictional character from the American television series I Love Lucy
