He writes that his poetry is strongly influenced by the music and poetry of Jamaica and what he calls "street politics". His first performance was in church when he was eleven, and by the age of fifteen, his poetry was already known among Handsworth's Afro-Caribbean and Asian communities.
He received a criminal record with the police as a young man and served a prison sentence for burglary. Tired of the limitations of being a black poet communicating with black people only, he decided to expand his audience, and headed to London at the age of twenty-two.
He became actively involved in a workers co-operative in Stratford, London, which led to the publication of his first book of poetry, Pen Rhythm (Page One Books, 1980). Three editions were published. Zephaniah has said that his mission is to fight the dead image of poetry in academia, and to "take everywhere" to people who do not read books so he turned poetry readings into concert-like performances.
His second collection of poetry, The Dread Affair: Collected Poems (1985), contained a number of poems attacking the British legal system. Rasta Time in Palestine (1990), an account of a visit to the Palestinian occupied territories, contained poetry and travelogue.
Zephaniah's first book of poetry for children, called Talking Turkeys, was reprinted after six weeks. In 1999 he wrote a novel for teenagers, Face, the first of four novels to date.
Zephaniah lived for many years in East London but in 2008 began dividing his time between Beijing and a village near Spalding, Lincolnshire. He was married for twelve years to Amina, a theatre administrator, whom he divorced in 2001. In 2011, Zephaniah accepted a year-long position as poet in residence at Keats House in Hampstead, London.
Zephaniah is a supporter of Aston Villa F.C. and is the patron for an Aston Villa supporters' website.
Zephaniah won the BBC Young Playwright's Award He has been awarded honorary doctorates by the University of North London (in 1998) the University of Central England (in 1999), Staffordshire University (in 2001) London South Bank University (in 2003), the University of Exeter and the University of Westminster (in 2006). On 17 July 2008 Zephaniah received an honorary doctorate from the University of Birmingham. He was listed at 48 in The Times' list of 50 greatest postwar writers.
He has released several albums of original music. He was awarded Best Original Song in the Hancocks 2008, Talkawhile Awards for Folk Music (as voted by members of Talkawhile.co.uk for his version of Tam Lyn Retold recorded with The Imagined Village. He collected the Award live at The Cambridge Folk Festival on 2 August 2008 and described himself as a "Rasta Folkie