John or Johnny Flynn may refer to:

• John Flynn (director) (1932–2007), American film director
• Johnny Flynn (born 1983), British actor and musician
• John Flynn (Marvel Cinematic Universe), fictional character

• John Flynn Jr. (born 1820), American politician in Wisconsin
• John E. Flynn (1912–2003), American politician from New York
• John Gerrard Flynn (born 1937), British ambassador to Venezuela, the Dominican Republic and Haiti, and Angola
• John Flynn (Australian politician) (born 1953), Australian politician
• John Flynn (New Brunswick politician) (born 1954)
• John Flynn (Irish politician) (died 1968), Fianna Fáil politician from Kerry
• John J. Flynn, former district attorney of Erie County, New York, chairman of the National District Attorneys Association

• John Flynn (baseball) (1883–1935), American baseball player
• John Flynn (rugby league) (1884–1918), English rugby league footballer
• John Flynn (cricketer) (1890–1952), Australian cricketer
• John Flynn (footballer, born 1948), English footballer
• John Flynn (Gaelic footballer) (born 1984), Irish Gaelic footballer

• John Flynn (minister) (1880–1951), Australian presbyterian minister and medical missionary
• John T. Flynn (1882–1964), American journalist
• John P. Flynn (1922–1997), United States Air Force general
• John J. Flynn, American labor union leader

• John Flinn (born 1954), American baseball player
• John Flinn (politician) (died c. 1900), Canadian politician and prison warden
• Jonny Flynn (born 1989), American basketball player
• John Flynt (1914–2007), American politician; U.S. Representative from Georgia