John G. Williams

John G. Williams may refer to:
 * John Williams (rugby union, born 1946), South African rugby player
 * John G. Williams (Canadian politician) (born 1946), Canadian politician
 * John G. Williams (ornithologist) (1913–1997), Welsh ornithologist
 * John G. Williams Jr. (1924–1991), American admiral
 * John Gary Williams, American musician
 * John Green Williams (1796–1833), American politician
 * John Griffith Williams (born 1944), Welsh judge