St John or St. John is a given name and surname. It can be pronounced /ˈsɪndʒɪn/ or /-ʒən/ sometimes in some places, particularly if it is the first part of a hyphenated family name or a given name. Use of the full stop separator (period) is uncommon in some countries, especially those that use Commonwealth English.

• St John Pettifor Catchpool (1890–1971), English Quaker relief worker
• St. John Ellis (1964–2005), British Rugby League player
• St John Ervine (1883-1971), Irish writer
• St John Groser (1890-1966), Anglican priest and Christian socialist
• St John Hornby (1867–1946), British businessman
• St John Horsfall (1910-1949), British motor racing driver
• St John Brodrick, 1st Earl of Midleton (1856–1942), British politician
• St John O'Neill (1741–1790), Irish MP for Randalstown
• Saint-John Perse, pseudonym of Alexis Leger (1887–1975), French poet and diplomat
• St John Philby (1885–1960), British civil servant and explorer in Arabia

• St. John Allerdyce, real name of Pyro, fictional supervillain
• St John Colchester, in the Torchwood audio drama series
• St. John Hawke, in the American TV series Airwolf
• St. John Quartermaine, in Quartermaine's Terms, the play by Simon Gray
• St. John Rivers, clergyman in Charlotte Brontë's Jane Eyre
• St. John Talbot, in the film Star Trek V: The Final Frontier
• St. John Powell, partner of fictional advertising firm Putnam, Powell and Lowe in American TV series Mad Men
• James St. John Smythe, alias used by fictional spy James Bond whilst posing as a horse buyer in A View to a Kill
• St. John Gurney-Clifford, in British TV series Grantchester

• Alex St. John, American programmer
• Al St. John, American comic actor
• Ambrose St. John (1815–1875), English priest and convert to Catholicism
• Andrew St. John, American actor
• Annie St John, British television presenter
• Archer St. John (1904–1955), American comic book publisher
• Austin St. John, American actor
• Bayle St. John, British writer
• Bert St. John, Australian tennis player
• Betta St. John, American actress
• Beverly St. John, American church elder
• Bridget St John, British singer
• Caroline St John-Brooks, English journalist
• Charles St. John, 19th-century U.S. Representative from New York
• Charles Edward St. John (1857–1935), American astronomer
• Cheryl St. John, American author
• Cornelia Laws St. John (died 1902), American poet
• Cynthia Morgan St. John (1852–1919), American Wordsworthian, book collector, and author
• Daniel B. St. John, 19th-century U.S. Representative from New York
• Dai St. John, Welsh heavyweight boxer
• David St. John, American poet
• Del St. John, Canadian hockey player
• Douglas St. John, New Zealand cricketer
• Earl St. John, American-born producer
• Edward St John (1916–1994), Australian politician
• Eugenia F. St. John, American evangelist and lecturer
• Florence St. John, English actress and singer
• Frederick St John, 2nd Viscount Bolingbroke
• George St John, 3rd Viscount Bolingbroke
• Georgie Boyden St. John (1861-1899), American composer
• Gina St. John, American actress
• Harold St. John, American botanist
• Harold Bernard St. John, Barbadian politician
• Helen St. John, American musician
• Henry St John, 1st Viscount Bolingbroke (1678–1751), English statesman and philosopher
• Henry St. John (congressman), 19th-century U.S. Representative from Ohio
• Henry Beauchamp St John, British Army officer
• Howard St. John, American actor
• Ian St John (1938–2021), Scottish footballer, manager and pundit
• Isaac M. St. John (1827–1880), Confederate States Army brigadier general during the American Civil War
• J. Allen St. John, American author, artist and illustrator
• James Augustus St. John (1795–1875), British author and traveller
• Jane Martha St. John (1801–1882), British amateur photographer
• Jill St. John, American film and television actress
• John St. John (disambiguation), several people
• Jon St. John, American voice actor and singer
• Joseph St. John, Canadian politician
• Jude St. John, Canadian football league player
• Julia St. John, English actress
• Kate St John, British musician and composer
• Kristoff St. John, American actor
• Lara St. John, Canadian violinist
• Locke St. John, American baseball player
• Lynn St. John, American sports coach
• Madeleine St John, Australian author
• Marco St. John, American actor
• Mark St. John, American guitarist
• Mary Louise St. John, American nun
• Mia St. John, American boxer
• Norman St John-Stevas, Baron St John of Fawsley, British politician
• Oliver St John (ca. 1598–1673), English statesman and judge
• Oliver St John (civil servant), British administrator of India
• Pat St. John, American DJ
• Patricia St. John, British writer
• Pete St. John, Irish singer
• Powell St. John, American singer and songwriter
• Ray St. John, British musician
• Richard Fleming St Andrew St John (1839–1919), English orientalist
• Robert St. John (1902–2003), American author, broadcaster, and journalist
• Scott St. John, Canadian musician
• Sharmagne Leland-St. John, Native American poet
• Spenser St. John, British Consul in Brunei (19th century)
• Trevor St. John, American actor
• Warren St. John, American author

Baronets of Lydiard Tregoze (1611)

• Sir John St John, 1st Baronet (1585–1648), Member of Parliament and prominent Royalist

Barons St John of Bletso (1559)

• John St John, 2nd Baron St John of Bletso (died 1596)
• Oliver St John, 5th Baron St John of Bletso
  • Oliver St John, 1st Earl of Bolingbroke (1580?–1646), known from 1618 until 1624 as 4th Baron St John of Bletso, English nobleman and politician
• Paulet St Andrew St John, 8th Baron St John of Bletso
• John St John, 11th Baron St John of Bletso (died 1757)
• John St John, 12th Baron St John of Bletso (died 1767)
• St Andrew St John, 14th Baron St John of Bletso
• St Andrew St John, 15th Baron St John of Bletso
• Beauchamp St John, 17th Baron St John of Bletso
• Mowbray St John, 19th Baron St John of Bletso
• John St John, 20th Baron St John of Bletso (1917–1976)
• Anthony St John, 22nd Baron St John of Bletso

• Alexandria St. John, in the American TV series The Vampire Diaries
• Dalton St. John, in the American TV series The Vampire Diaries
• Deacon St. John, protagonist in the video game Days Gone
• Mick St. John, one of the main characters in the American TV series Moonlight
• Peter St. John (Mandala), in the British comic book series Zenith
• Lorenzo St. John, a vampire in the American TV series The Vampire Diaries
• Virginia St. John, in the American TV series The Vampire Diaries

• All pages with titles containing St John
• Matthias Sention, Sr. (1603–1669), founding settler of Norwalk, Connecticut and ancestor of many people with the surname St. John in America
• St John-Mildmay Baronets
• St John Baronets, of Northwood (1660)
• Viscount Bolingbroke