John, Johnny, Jack, Jackie, or Jock Simpson may refer to:
John Simpson (Parliamentarian), politician of the post-English Civil War period, see Thomas Kelsey
John Simpson (Kentucky), American Congressman-elect, see Kentucky in the War of 1812
John Simpson (MP) (1763–1850), English politician, Member of Parliament for Wenlock
John Simpson (Quebec politician) (1788–1873), government official and politician in Quebec
John Simpson (Canada West politician) (1807–1878), Canadian businessman and politician
John Simpson (Ontario politician) (1812–1885), Ontario banker and member of the Senate of Canada
John A. Simpson (1854–1916), Canadian politician
John Thomas Simpson (1870–1965), Conservative member of the Canadian House of Commons
Jack Simpson (politician) (born 1929), Australian politician
John Simpson, bassist in the American R&B band The SOS Band
John Simpson (artist) (1782–1847) was a British painter who painted The Captive Slave
John Simpson (actor/producer), Canadian actor
Sir John William Simpson (1858–1933), English architect
John Simpson (architect) (born 1954), British modern-day classical architect
John Palgrave Simpson (1807–1887), Victorian playwright
John L. Simpson (born 1963), Australian film and theatre producer, writer and distributor
John Simpson (journalist) (born 1944), BBC journalist, foreign correspondent and author
John Baird Simpson (1894-1960), Scottish geologist
John B. Simpson (born 1947), former president of the University at Buffalo
John Wistar Simpson (1914–2007), American electrical engineer
John Simpson (lexicographer) (born 1953)
John Alexander Simpson (1916–2000), physicist
Jack Simpson (1858–1895), Scottish golfer
Jock Simpson (1886–1959), England and Blackburn Rovers footballer
John Simpson (footballer, born 1918) (1918–2000), English footballer, played for Huddersfield Town and York City
John Simpson (footballer, born 1933) (1933–1993), English footballer, played for Lincoln City and Gillingham
Jackie Simpson (defensive back) (born 1934), American football player
Jackie Simpson (linebacker) (1936–1983), linebacker
John Simpson (boxer) (born 1983), Scottish featherweight boxer
John Simpson (English cricketer) (born 1988), English cricketer
John Simpson (New Zealand cricketer) (1907-1980), New Zealand cricketer
John Simpson (fencer) (born 1927), Australian Olympic fencer
John Simpson (basketball), professional basketball player
Johnny Simpson (1922–2010), New Zealand rugby union player
John Simpson (soldier) (1748–1825), American Revolutionary War soldier at the Battle of Bunker Hill
John Simpson (VC) (1826–1884), Scottish recipient of the Victoria Cross
John Simpson Kirkpatrick (1892–1915), Australian World War I war hero (who enlisted as "John Simpson")
John Herbert Thomas Simpson (1907–1967), senior RAF officer in the mid-1950s and eighth Commandant Royal Observer Corps
John Simpson (British Army officer) (1927–2007), British Army officer and Director SAS
John Simpson (journalist/consumer advocate) (born 1948), American consumer rights advocate and former journalist
John Simpson (martyr), one of the Marian martyrs
Rev. John Simpson (Presbyterian) (1740–1808), of South Carolina, in the American Revolutionary War
Rev. John Simpson (Unitarian) (1746–1812), of Bath, English Unitarian minister and religious writer
John Woodruff Simpson (1850–1920), American lawyer and founding partner at Simpson Thacher & Bartlett
Sir John Hope Simpson (1868–1961), English administrator in India
John D. Simpson (1901–1988), Canadian businessman in the Canadian Mining Hall of Fame
John Milton Bryan Simpson (1903–1987), American judge
John Simpson (police official) (born 1932), former director of US Secret Service and Interpol
John Simpson (journalist) (born 1944), BBC journalist and world affairs editor
John Simpson (priest) (born 1933), Anglican clergyman
John Baird Simpson (1894–1960), Scottish geologist
John Chandler Simpson, a fictional character in Eric Flint's alternate history book series 1632
