Oliver Brendan Jeffers MBE (born 1977) is an Australian-born Northern Irish artist, illustrator and writer.

[1] From figurative painting and installation, to illustration and picture-book making, his work has been exhibited in New York, The Brooklyn Museum, Berlin, Dublin, London, Sydney, Washington, D.C., and Belfast.

His solo show Additional Information, (Belfast December 2006) studied the balance between form and content by drawing parallels between the arts and sciences, in which figurative oil paintings were over laid with mathematical equations.

As a co-founder of the art collective OAR, along with Rory Jeffers, Mac Premo and Duke Riley, their exhibitions include 9 Days in Belfast, book and the award-winning BUILDING.

Lost and Found became Jeffers' first book to be made into animation by London-based Studio AKA, premiering on Christmas Eve 2008 on Channel 4.

[12] and Jeffers Illustration book Here We Are: Notes for Living on Planet Earth is adapted to a short film by Apple TV+.