John or Jack Phelan may refer to: John J. Phelan (1851–?), Supreme Knight of the Knights of Columbus and Secretary of the State of Connecticut John Paul Phelan (born 1978), Irish Fine Gael politician John Henry Phelan (1877–1957), secretary-treasurer of the Yount-Lee Oil Company John Leddy Phelan, Beveridge Award-winning author of The People and the King: The Comunero Revolution in Colombia, 1781 John J. Phelan, Jr., American financier who served as president and later chairman and chief executive of the New York Stock Exchange John Dennis Phelan (1809–1879), jurist and politician in the southern United States Jack Phelan (basketball, born 1925), American professional basketball player for the Waterloo Hawks and Sheboygan Red Skins Jack Phelan (basketball, born 1954), American college basketball coach of the University of Hartford