Born into a working-class family, Michael Leunig spent his formative years in the industrial western suburbs of Melbourne. During his childhood he displayed a 'flair for the creative' with drawing being one of his favourite pastimes. Described as 'a quiet, introspective man who shuns the limelight', from an early age Leunig was recognised for his 'individuality', 'inherent gentleness' and 'playful sense of mischief'.
Conscripted into the army during the Vietnam War, he was rejected on physical grounds and subsequently enrolled at Swinburne Film and Television School. While freelancing as an artist, he spent the following two years at Swinburne before leaving his studies to work as a political cartoonist for an afternoon newspaper called Newday. When the paper folded after six months, Leunig moved to Nation Review and it was while he was working for this publication that the cartoonist defined the distinctive drawing style which has been synonymously associated with his name. Creating an off-beat world which often conveys a sense of pathos, Leunig inhabited his cartoons with a collection of whimsical figures which ranged from playful ducks and forlorn dogs, to the iconic 'Leunig' characters of Mr Curly and Vasco Pyjama.
While Leunig was seen primarily as a cartoonist in publications such as A Bag of Roosters (1983) and Why Dogs Sniff Each Other's Tails (1998), many of his 'thought-provoking' books also contained poetry, prose, short stories and prayers. His work appeared in a wide array of publications, he was a regular contributor to the Melbourne Age, and his illustrations accompanied the text of many different writers. Reproduced on consumer merchandise (e.g. calendars, t-shirts and posters), the 'Leunig' cartoon not only secured a place in Australian popular culture but also gained prominence overseas. In both England and the USA, the cartoonist attained 'cult status'; notably a Vermont restaurant, 'Leunig's Bistro', was named after him.
Leunig's work also inspired stage productions. In 1991, the character of Vasco Pyjama was featured in a stage adaptation, 'The Voyage of Vasco Pyjama', which was scripted by Ingle Knight, and in 1993 another play based on Leunig's work, 'State of Bewilderment', was produced in the United Kingdom and Australia. A dance work 'Look Right Through Me', choreographed by Kate Denborough and inspired by Leunig's work, was performed in 2011.
He is the brother of the artist and cartoonist, Mary Leunig.