Dan, Danny, or Daniel Sullivan may refer to:

• Daniel J. Sullivan (born 1940), American film and theater director
• Daniel G. Sullivan, American screenwriter
• Dan Sullivan (musician), indie rock musician
• Dan Panic, American punk rock drummer, real name Dan Sullivan
• Daniel Sullivan (countertenor) (died 1764), Irish opera singer
• Dan Sullivan (critic) American theater critic
• Daniel Sully, American actor (1855-1910), born "Daniel Sullivan"

• Dan Sullivan (Anchorage mayor) (born 1951), Republican former mayor of Anchorage, Alaska
• Dan Sullivan (U.S. senator) (born 1964), Republican U.S. Senator from Alaska
• Daniel V. Sullivan (1886–1966), New York judge and district attorney
• Dan Sullivan (Arkansas politician), member of Arkansas State Senate
• Dan Sullivan (Oklahoma politician) (born 1963), member of the Oklahoma House of Representatives

• Dan Sullivan (New Zealand politician) (1882–1947), New Zealand politician
• Dan Sullivan (Australian politician) (born 1960), from Western Australia

• Dan Sullivan (baseball) (1857–1893), 19th-century Major League Baseball player
• Dan Sullivan (American football) (born 1939), former Baltimore Colts offensive lineman
• Daniel Sullivan (ice hockey, born 1947), former World Hockey Association goaltender
• Danny Sullivan (born 1950), American race car driver
• Danny Sullivan (rugby league) (born 1982), Australian rugby league player
• Danny Sullivan (tennis) (born 1952), South African tennis player.
• Daniel Sullivan (American football), head college football coach for the Eureka College Red Devils
• Dan Sullivan (ice hockey, born 1981), Canadian ice hockey player
• Daniel Sullivan (ice hockey, born 1987), Canadian-born Italian ice hockey defenceman
• Danny Sullivan (footballer) (born 1994), association footballer for Torquay United F.C.

• Danny Sullivan (technologist) (born 1965), American search engine expert
• Daniel Sullivan (Great Chicago Fire), American involved in the Great Chicago Fire
• Daniel Augustus Joseph Sullivan (1884–1941), American naval officer; Medal of Honor recipient
• Daniel Sullivan (entrepreneur), American entrepreneur and business executive
• Daniel Sullivan (frontiersman) (died 1790), 18th-century military figure in the North American frontier
• Daniel "Horse-Whisperer" Sullivan (died 1810), Irish horse trainer
• Daniel Y. Sullivan (1948–2012), American dentist

• Dan Sullivan (EastEnders), a character from the BBC soap opera EastEnders
• Danny Sullivan (Dream Team), a character from the British television series Dream Team