Born in Georgetown, Guyana, McWatt studied at the University of Toronto (1966-70) and at Leeds University, where he completed a Ph.D. in 1975. He subsequently headed the English Department at the University of the West Indies, Cave Hill campus, Barbados.
McWatt has published three collections of poetry, the second of which, The Language of Eldorado (1994), was awarded the Guyana Prize. His first work of fiction, Suspended Sentences (2005), was the winner of a Commonwealth Writers' Prize in 2006, as well as the Casa de las Américas Prize for best book of Caribbean Literature in English or Creole.
His poetry has been much published in little magazines and he has contributed widely to journals on aspects of Caribbean literature. He was founding editor, in 1986, of the Journal of West Indian Literature. He is co-editor (with Stewart Brown) of the Oxford Book of Caribbean Verse (2005) and with Lucy Evans and Emma Smith of The Caribbean Short Story: Critical Perspectives (2011).
- Interiors - Dangaroo Press, 1989
- The Language of Eldorado — 1994
- The Journey to Le Repentir - Peepal Tree Press, 2009
- Suspended Sentences: Fictions of Atonement — Peepal Tree Press, 2005
- The Oxford Book of Caribbean Verse — 2005 (edited with Stewart Brown)
- The Caribbean Short Story: Critical Perspectives — Peepal Tree Press, 2011
- Lucy Evans, "Landscape and Identity - Re-encountering Guyana in an interview with Mark McWatt", Kaieteur News, 27 September 2009.