Donald Duncan or Don Duncan may refer to:
Donald B. Duncan (1896–1975), American naval officer Donald W. Duncan (1930–2009), American soldier and anti-war activist Donald F. Duncan Sr. (1892–1971), American toy manufacturer and inventor Donald Keith Duncan, Jamaican dental surgeon and politician Donald A. Duncan, American swimming coach
See also Joe Don Duncan (born 1990), American football player
Duncan (surname)