John Clarke may refer to:
- John Clarke Whitfield (1770–1836), English organist and composer
- John Sleeper Clarke (1833–1899), American/British actor and manager
- John Louis Clarke (1881–1970), Blackfoot wood carver from Montana
- John S. Clarke (1885–1959), British lion tamer, politician, poet, newspaper editor and art expert
- Bryan Forbes or John Theobald Clarke (1926–2013), English film director, screenwriter, film producer, actor and novelist
- John Clarke (actor) (1931–2019), American soap opera actor from Days of Our Lives
- John Clarke (poet) (1933–1992), American poet
- John Clem Clarke (1937–2021), American painter and graphic artist
- John Clarke (satirist) (1948–2017), New Zealand/Australian satirist and actor
- John Cooper Clarke (born 1949), British performance poet, active since the late 1970s
- John Clarke (museum curator) (1954–2020), British museum curator, expert in Ladakhi and Tibetan metalwork
United States
- John Hopkins Clarke (1789–1870), U.S. Senator from Rhode Island, 1847–1852
- John Clarke (Michigan politician) (1797–1876), American businessman, farmer, and politician
- John Jones Clarke (1803–1887), American politician in the Massachusetts legislature
- John C. Clarke (1831–1906), American politician in the Wisconsin legislature
- John Blades Clarke (1833–1911), U.S. representative from Kentucky, 1875–1876
- John Proctor Clarke (1856–1932), judge in New York State
- John Hessin Clarke (1857–1945), associate justice of the US Supreme Court
- John D. Clarke (1873–1933), U.S. representative from New York, 1921–1924 and 1927–1934
- John Clark (Georgia governor) (sometimes spelled Clarke; 1766–1832), Governor of Georgia from 1819 to 1823
- John Clarke (Baptist minister) (1609–1676), co-founder of Rhode Island
- John Clarke (dean of Salisbury) (1682–1757), dean of Salisbury Cathedral, mathematician and natural philosopher
- John Clarke (Congregationalist minister) (1755–1798), minister, First Church, Boston, Massachusetts
- John Clarke (Baptist missionary) (1802–1879), author of Specimens of Dialects
- J. Richard Clarke (born 1927), leader in The Church of Jesus Christ of Latter-day Saints
- John Clarke (bishop) (born 1938), retired bishop of the Anglican Church of Canada
- John Clarke (dean of Wells) (born 1952), Dean of Wells 2004–15
- John Clarke (provost) (died 1781), provost of Oriel College, Oxford
- John Henry Clarke (1853–1931), English classical homeopath
- John Mason Clarke (1857–1925), American paleontologist from New York
- John L. Clarke (1905–1991), served as president of Ricks College
- John Henrik Clarke (1915–1998), self-taught scholar who became an authority on African history and an advocate for Black Studies
- John Frederick Clarke (1927–2013), English aeronautical engineer
- John Clarke (physician, 1582–1653), English physician
- John Clarke (physician, 1761–1815), English physician and obstetrician
- John Clarke (physicist) (born 1942), English physicist at University of California at Berkeley
- John Clarke (mountaineer) (1945–2003), Canadian mountaineer, explorer and wilderness educator
- John R. Clarke (scientist) (born 1945), serves as Scientific Director at the United States Navy Experimental Diving Unit
- John R. Clarke (historian), Professor in Fine Arts at the University of Texas at Austin
- John T. Clarke, (born 1952), American astronomer
- John Erskine Clarke (1827–1920), British rower and clergyman who founded the first parish magazine
- John Clarke (Australian cricketer) (1829–1872)
- John Clarke (Scottish footballer) (fl. 1890s), footballer who played for Bury, Blackpool and Luton Town
- John Clarke (English footballer) (fl. 1910s–1920s), English football forward
- John Clarke (rugby league) (fl. 1930s–1940s), Australian rugby league player
- John Clarke (cricketer, born 1948), English cricketer
- John Clarke (rugby union) (born 1975), New Zealand-born Samoan rugby union player
- John Clarke (Gaelic footballer) (fl. 2000s), Gaelic footballer for Down
- John Clarke (sailor) (1934–2022), Canadian Olympic sailor
- John Clarke (hurler), Irish hurler
- John Clarke (footballer, born 2004), English footballer