Dorgan was born in Cork in 1953 and educated in North Monastery School. He completed a BA in English and Philosophy and a MA in English at University College Cork, after which he tutored and lectured in that University, while simultaneously Literature Officer with Triskel Arts Centre in Cork. He was visiting faculty at University of Southern Maine.
He lives in Dublin with his partner, the poet and playwright Paula Meehan.
After Theo Dorgan's first two collections, The Ordinary House of Love and Rosa Mundi, went out of print, Dedalus Press reissued these two titles in a single volume What This Earth Cost Us. He has also published a selected poems in Italian, La Case ai Margini del Mundo, (Faenza, Moby Dick, 1999).
Dorgan has edited The Great Book of Ireland (with Gene Lambert, 1991); Revising the Rising (with Máirín Ní Dhonnachadha, 1991); Irish Poetry Since Kavanagh (Dublin, Four Courts Press, 1996); Watching the River Flow (with Noel Duffy, Dublin, Poetry Ireland/Éigse Éireann, 1999); The Great Book of Gaelic (wiith Malcolm Maclean, Edinburgh, Canongate, 2002); and The Book of Uncommon Prayer (Dublin, Penguin Ireland, 2007).
He has been Series Editor of the European Poetry Translation Network publications and Director of the collective translation seminars from which the books arose.
A former Director of Poetry Ireland/Éigse Éireann, he has worked extensively as a broadcaster of literary programmes on both radio and television. His Jason and The Argonauts, to music by Howard Goodall, was commissioned by and premiered in the Royal Albert Hall in 2004. He was the scriptwriter for the acclaimed TV documentary series Hidden Treasures, and a series of texts commissioned from him features in the dance musical Riverdance. His songs have been recorded by a number of musicians, including Alan Stivell, Jimmy Crowley and Cormac Breathnach. He was presenter of Poetry Now on RTÉ Radio 1, and later presented RTÉ's TV books programme, "Imprint".
Among his awards are the Listowel Prize for Poetry, 1992 and the O'Shaughnessy Prize for Irish Poetry 2010. A member of Aosdána, he was appointed to The Arts Council / An Chomhairle Ealaíon in 2003. He also served on the Board of Cork European Capital of Culture 2005.
He was also awarded the 2015 Poetry Now Award for Nine Bright Shiners.
- The ordinary house of love, Salmon Pub., 1990, ISBN 9780948339509
- Rosa Mundi, Salmon poetry, 1995, ISBN 9781897648643
- La casa ai margini del mondo., Translated by M. Giosa, Mobydick, 1998, ISBN 9788881780761
- Sappho's Daughter, Wave Train Press, 1998, ISBN 9780953192304
- La Hija de Safo, Translated by Francisco Castaño, Hiperión Ediciones, 2001, ISBN 9788475176970
- What This Earth Cost Us, Dedalus Press, 2008, ISBN 9781904556947
- Greek, Dedalus Press, 2010, ISBN 9781906614171
- Making Way, New Island Books, 2013, ISBN 9781848402249
- Nine Bright Shiners, Dedalus Press, 2014, ISBN 9781906614980
- Sailing for home: a voyage from Antigua to Kinsale, Penguin Ireland, 2004; Penguin Ireland, 2005, ISBN 9781844880492; Dedalus Press, 2010, ISBN 9781906614331
- Time on the Ocean: A Voyage From Cape Horn to Cape Town, New Island Books, 2010, ISBN 9781848400757
- A Book of Uncommon Prayer. Penguin Books Limited. 5 June 2008. ISBN 978-0-14-191726-9.
- Preghiere non-comuni, Armenia (1 January 2009) ISBN 978-8834422380
- Songs of earth and light, Barbara Korun, Southword Editions, 2005, ISBN 9781905002061
- Dedalus Press – poetry matters
- The Arts Council / An Chomhairle Ealaíon: Council Members
- Irish Times, Poetry Now Award 2015
- William Stewart, Steven Barfield, British and Irish poets: a biographical dictionary, 449–2006, McFarland, 2007, ISBN 9780786428915