After studying fine art and then chemical engineering for 2 years at the Cork Institute of Technology, Ireland, Michael O'Sullivan went on to take BA (English and Psychology) and MA (English) degrees at the National University of Ireland, Cork. He then received an EAP scholarship to study at the graduate school of English at the University of California, Berkeley for the 2000/2001 academic year. He completed his PhD at the National University of Ireland, Cork in 2004 after being awarded an Irish Research Council for the Humanities and Social Sciences award for 2001-2003. He has taught on language and literature for the National University of Ireland, Cork, the Open University in the UK, the Upward Bound Program of the University of California, Berkeley, The Nagoya University of Commerce and Business, Japan and The Chinese University of Hong Kong. He is currently Associate Professor in English at the Chinese University of Hong Kong.

His research interests include literary modernism, literary theory and philosophy, literature and religion, and the philosophy of education. His monographs and edited collections include the following: The Humanities and the Irish University (forthcoming) (Manchester University Press), Weakness: a literary and philosophical history (Continuum), The Incarnation of Language: Joyce, Proust and a philosophy of the flesh (Continuum), Michel Henry: Incarnation, Barbarism, and Belief (Peter Lang), Affecting Irishness: Negotiating Cultural Identity within and beyond the Nation (Peter Lang), and Beckett Re-Membered: After the Centenary (Cambridge Scholars Publishing). He has also published widely on literature and related fields in such journals as Parallax, Mosaic, Textual Practice and Nottingham French Studies.

He has convened (with colleagues) a number of international conferences, including Affecting Irishness (Trinity College, Dublin, 2004), an international Beckett conference at the National University of Ireland, Cork, in 2006, and the forthcoming conference "The Future of English in Asia" to be held at the Chinese University of Hong Kong in 2013. For the past two years he has been the research convenor at the English department of the Chinese University of Hong Kong. In this time he has organized over 30 research seminars for local and international speakers.