Duncan may refer to:

People

* Duncan (given name), various people * Duncan (surname), various people * Clan Duncan * Justice Duncan (disambiguation)

Places

* Duncan Creek (disambiguation) * Duncan River (disambiguation) * Duncan Lake (disambiguation), including Lake Duncan

Australia

*Duncan, South Australia, a locality in the Kangaroo Island Council *Hundred of Duncan, a cadastral unit on Kangaroo Island in South Australia

Bahamas

*Duncan Town, Ragged Island, Bahamas ** Duncan Town Airport

Canada

* Duncan, British Columbia, on Vancouver Island * Duncan Dam, British Columbia * Duncan City, Central Kootenay, British Columbia; see List of ghost towns in British Columbia * Mount Duncan, in the Selkirk Mountains

United States

* Duncan Township (disambiguation) * Duncan, Arizona * Duncan, Iowa * Duncan, Kentucky (disambiguation) * Duncan City, Cheboygan, Michigan * Duncan, Mississippi * Duncan, Missouri * Duncan, Nebraska * Duncan, North Carolina * Duncan, Oklahoma * Duncan, South Carolina * Fort Duncan, Eagle Pass, Texas

Brands and enterprises

* Duncan (mango), a named mango variety selected and patented in Florida * Duncan Toys Company, manufacturer of yo-yos and other toys * Seymour Duncan, a manufacturer of guitar pickups and effects pedals

Music

* Duncan (Paul Simon song), "Duncan" (Paul Simon song) * Duncan (Slim Dusty song), "Duncan" (Slim Dusty song) * "Duncan", a song by Sarah Slean on the album ''Night Bugs''

Ships

* HMS Duncan, HMS ''Duncan'' (multiple) * USS Duncan, USS ''Duncan'' (multiple)

Other uses

*Duncan (horse)