Sir John McEwen (born March 29, 1900, Chiltern, Vic., Australia—died Nov. 21, 1980, Melbourne) was a farmer, politician, and prime minister of Australia from Dec. 19, 1967, to Jan. 10, 1968.
A member of the House of Representatives (1934–71), McEwen served in several ministerial posts during World War II, including deputy prime minister (1958–71), and was acting prime minister for three weeks upon the death of Prime Minister Harold Holt in 1967. McEwen was knighted in 1971.