Dr. Dennis John Duncanson (sometimes referred to as John Dennis Duncanson) (26 May 1917 - 15 April 1998) was a British Overseas Civil Servant and academic who specialised in Asian studies. Duncanson had extensive experience of the Indian Ocean area, from East Africa to China. After joining the Colonial Service, Duncanson became aide-de-camp to the Governor of Hong Kong, and subsequently joined the administration in what was then Malaya. In 1961, Duncanson was invited to join the British Advisory Mission in Saigon and worked as Counsellor in Aid at the British Embassy in Saigon during the mid-sixties, being later awarded an OBE.
On returning to England, Duncanson joined the staff of the University of Kent at Canterbury, where he became Reader, and set up the Centre for South-East Asian Studies. His book, Government and Revolution in Vietnam was written whilst the Vietnam War was still in progress, and found its place as recommended reading in politics and government at several universities.
In 1969, Duncanson was elected to the Council at the Royal Asiatic Society, and in 1977 became its Director. He was President in 1982-5, and served another two terms as Director in 1986-9 and 1992-5. He died in 1998 at Osborne House in the Isle of Wight.