John Diefenbaker (1895–1979) was the 13th prime minister of Canada, serving as such from 1957 to 1963.
Diefenbaker may also refer to the following namesakes of the prime minister:
Diefenbaker Canada Centre, archive and library in Saskatoon, Canada
Diefenbaker the wolf, an animal character in the television series Due South Lake Diefenbaker, a Canadian lake Saskatoon John G. Diefenbaker International Airport, a Canadian airport
See also The Canadian Coast Guard polar icebreaker was initially to be named John G. Diefenbaker.