Graham Robert Oppy (born 1960) is an Australian philosopher whose main area of research is the philosophy of religion. He is Professor of Philosophy and Associate Dean of Research at Monash University, CEO of the Australasian Association of Philosophy, Chief Editor of the Australasian Philosophical Review, Associate Editor of the Australasian Journal of Philosophy, and is on the editorial boards of Philo, Philosopher's Compass, Religious Studies, and Sophia.^[3] He was elected Fellow of the Australian Academy of the Humanities in 2009.^[4] Graham Oppy is widely considered by some philosophers to be the most formidable defender of Atheism living today. ^[5]

Graham Oppy was born in Benalla on 6 October 1960 to a Methodist family, but he ceased to be a religious believer as a young teenager,^[6] and is now an atheist.^[7] His family moved to Ballarat in 1965 and had his secondary schooling at Wesley College, Melbourne.^[8] He attended Melbourne University from 1979, where he completed two degrees: a BA (Hons) in philosophy and a BSc in mathematics. In 1987 he started graduate work at Princeton University under the supervision of Gilbert Harman on questions in the philosophy of language.^[6]

He was a lecturer at the University of Wollongong from 1990 to 1992 and after doing a post-doc at the Australian National University, he moved to Monash as a senior lecturer, and was promoted to professor in 2005. He is currently Associate Dean of Research (since 2004) and Associate Dean of Graduate Studies in the Faculty of Arts at Monash University.^[6]

• Ontological Arguments and Belief in God, 1996. ISBN 0-521-48120-1.
• Philosophical Perspectives on Infinity, 2006. ISBN 0-521-86067-9.
• Arguing About Gods, 2006. ISBN 0-521-86386-4.
• "Evolution vs Creationism in Australian Schools", chapter in The Australian Book of Atheism, 2010. ISBN 978-1-921640-76-6.
• The Best Argument against God, 2013. ISBN 978-1-137-35413-6
• Reinventing Philosophy of Religion: An Opinionated Introduction, 2014. ISBN 978-1-137-43455-5
• Describing Gods: An Investigation of Divine Attributes, 2014. ISBN 978-1-107-08704-0
• The Routledge Handbook of Contemporary Philosophy of Religion (Routledge Handbooks in Philosophy), 2017. ISBN 978-1-138-57405-2
• Atheism and Agnosticism (Elements in the Philosophy of Religion), 2018. ISBN 978-1-108-45472-8
• Atheism: The Basics, 2018. ISBN 978-1-138-50696-1
• Naturalism and Religion: A Contemporary Philosophical Investigation (Investigating Philosophy of Religion), 2018. ISBN 978-0-815-35466-6
• (with Joseph Koterski) Theism and Atheism: Opposing Arguments in Philosophy, 2018. ISBN 978-0028664453
• A Companion to Atheism and Philosophy (Blackwell Companions to Philosophy), 2019. ISBN 978-1-119-11911-1
• Is There a God?: A Debate (Little Debates about Big Questions), 2021. ISBN 978-0367243944