John Barnett

John Barnett may refer to:

• John Barnett (Australian rules footballer) (born 1975), former Australian rules footballer
• John Barnett (composer) (1802–1890), English composer
• John Barnett (rugby) (1880–1918), Australian rugby union and rugby league player
• John Francis Barnett (1837–1916), English music composer and teacher
• John Davis Barnett (1848–1926), early Canadian curator-librarian
• Jack Barnett (baseball) (1879–1923), American baseball player
• John Maughan Barnett (1867–1938), New Zealand organist, choirmaster and conductor
• John T. Barnett (1851–1935), American colonel
• John W. Barnett (1800–1876), American farmer, merchant and community leader
• John Manley Barnett (1917–2013), American conductor
• John Barnett (producer) (1945–2025), New Zealand film and television producer
• John Barnett (whistleblower) (1962–2024), Boeing whistleblower