John Stewart Duncan OBE (born 17 April 1958) is a British diplomat.

In June 2013, he was appointed by Queen Elizabeth II on the advice of the British government, to represent the Queen as Governor of the British Virgin Islands, and to act as the de facto head of state in the Territory.

He joined the Foreign and Commonwealth Office (FCO) in 1980 and served in Paris and Khartoum and in various positions at the FCO before being posted to Tirana where he was chargé d'affaires 1992–1993 (the UK and Albania did not exchange ambassadors until 1996).

He gave a keynote address at "Gov 2.0 L.A." in Los Angeles on 12 February 2011.

[3] He was British chief diplomat and Special Representative for a London Conference on Cyberspace held on 1 and 2 November 2011.