John Harlan may refer to:
John Marshall Harlan (1833–1911), US Supreme Court Justice, 1877–1911
John Marshall Harlan II (1899–1971), US Supreme Court Justice, 1955–1971, grandson of the pre-World War I justice
John Harlan (announcer) (1925–2017), American television announcer
John Maynard Harlan (1864–1934), American lawyer and politician in Chicago