Adam Duncan may refer to:
Adam Duncan, 1st Viscount Duncan (1731–1804), British admiral Adam Haldane-Duncan, 2nd Earl of Camperdown (1812–1867), British politician Adam Duncan (sailor) (1833–?), sailor in the Union Navy in the American Civil War, recipient of the Medal of Honor Adam Duncan (cricketer) (1852–1940), English lawyer and cricketer Scott Duncan (footballer) (Adam Scott Mathieson Duncan, 1888–1975), Scottish footballer and manager Adam M. Duncan (1927–2000), member of the Utah state legislature Adam Lewis Duncan, American politician, member of the South Carolina House of Representatives