John Mullen may refer to:
- John Mullen (catcher), baseball player
- John Mullen (baseball executive) (died 1991)
- John J. Mullen (American football), football coach
- John J. Mullen (mayor), politician
- John Kernan (J.K.) Mullen, Irish-American businessman, philanthropist
See also
- John Mullens (1896–1978), Australian politician
- John McMullen (disambiguation)
