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
See also John Williams (disambiguation)