John Fay

John Fay may refer to:
 * John Fay (American football) (1895–1983), American football player
 * John D. Fay (1815–1895), American civil engineer
 * John Fay (politician) (1773–1855), American politician
 * John J. Fay Jr. (1927–2003), American politician in New Jersey
 * John Fay (writer) (21st century), British television writer
 * John David Fay, mathematician, eponym of Fay's trisecant identity