Duncan Suttles (born 21 December 1945) is a Grandmaster (chess) of chess who was the strongest Canadian player between the eras of Abe Yanofsky and Kevin Spraggett.
He is one of the few over-the-board grandmasters who also holds the title of Grandmaster of International Correspondence Chess.
Suttles has been inactive in over-the-board play since the mid-1980s.
He currently serves with the software firm Magnetar Games, as President and Chief Technologist.