United States •
John Gardner (Rhode Island governor) (1697–1764), deputy governor, Colony of Rhode Island •
John Gardner (Continental Congress) (1747–1808), farmer, Rhode Island delegate to Continental Congress •
John A. Gardner, American physicist and developer of
Gardner–Salinas braille codes •
John Fentress Gardner (1912–1998), American author and educator •
John J. Gardner (1845–1921), politician representing New Jersey in the House of Representatives, 1885 to 1893 •
John W. Gardner (1912–2002), U.S. Secretary of Health, Education, and Welfare during the Great Society •
John P. Gardner (1922–1994), judge and politician in South Carolina
Elsewhere •
John Gardner (Australian politician) (born 1979), Australian Liberal Party MP for the South Australian seat of Morialta since 2010 •
John Gardner (legal philosopher) (1965–2019), formerly professor of jurisprudence at the University of Oxford, England, UK •
John Dunn Gardner (1811–1903), British Member of Parliament, 1841 to 1847 ==Sport==