Miller was born and raised in Kingston, Jamaica. He attended the University of the West Indies, but dropped out short of graduation. However, while studying there, he befriended Mervyn Morris, who encouraged his writing. Afterward, Miller began publishing widely throughout the Caribbean. In 2004, he left for England to study for an MA in Creative Writing (The Novel) at Manchester Metropolitan University under the tutelage of poet and scholar Michael Schmidt. In 2006, his first book of poetry was released, Kingdom of Empty Bellies. It was shortly followed by a collection of short stories, The Fear of Stones, which explores the issue of Jamaican homophobia. It was shortlisted in 2007 for a Commonwealth Writer's Prize in the category of Best First Book (Canada or Caribbean) Shortlist 2007. His second collection of poetry, There Is an Anger That Moves, was published in 2007 by Carcanet Press Carcanet Press - Kei Miller.
Miller divides his time between Jamaica and the United Kingdom, where he teaches Creative Writing at the University of Glasgow.