He studied at the University of London, first at Goldsmiths' College, then at King's College London. In 1982, he moved to Cornell University in upstate New York, where he was Assistant Professor and then Associate Professor. In 1994 he came back to England to become a Lecturer in Music (later Professor) and Fellow of St Hugh's College, Oxford. In 1999 he became Professor of Music at Cambridge University, where he was a Fellow of St John's College and (in 2005-06) Chair of the School of Arts and Humanities. In 2002 he was the Visiting Ernest Bloch Lecturer at the University of California, Berkeley; in 2007 he was a visiting scholar at the Institute for Advanced Study in Princeton. 
Roger Parker's work has centred on opera, in particular Italian opera of the nineteenth century. For ten years he was founding co-editor (with Arthur Groos) of the Cambridge Opera Journal, and he continues as General Editor (with Gabriele Dotto) of the The Critical Edition of the Operas of Gaetano Donizetti published by Casa Ricordi of Milan.
- A History of Opera (with Carolyn Abbate), (Penguin, 2012)
- The New Grove Guide to Verdi and his Operas (Oxford: Oxford University Press, 2007)
- Remaking the Song: Operatic Visions and Revisions from Handel to Berio (Berkeley & Los Angeles: University of California Press, 2006)
- “The Opera Industry”, in Jim Samson, ed., The Cambridge History of Nineteenth-Century Music (Cambridge, 2002), 87-117
- "Philippe and Posa Act II: The Shock of the New", Cambridge Opera Journal, 14/1-2 (2002), 133-47
- "Gaetano Donizetti, Le convenienze ed inconvenienze teatrali", in Le opere di Gaetano Donizetti (Milan: Ricordi, 2002; vocal score, 2003). Joint editor with Anders Wiklund
- Pensieri per un maestro: Studi in onore di Pierluigi Petrobelli (Turin: Einaudi, 2002). Joint editor with Stefano La Via
- Professor Roger Parker: biography on kcl.ac.uk
- Prof. Roger Parker's past lectures on music at Gresham College. Available as audio/video files and as transcripts. Retrieved 23 December 2013.