Descended from German, English and Irish immigrants who arrived in Australia in the 1830s and 1840s, Christopher Koch was born in Hobart, Tasmania, in 1932 and educated at Clemes College, St Virgil's College, Hobart High School and the University of Tasmania. After graduating, Koch joined the Australian Broadcasting Corporation as a cadet journalist. Since then he has had a variety of occupations and has lived and worked in Europe, America and Asia. He was a producer for the ABC, with responsibility for radio broadcasts for schools, for ten years. In 1972/3 he resigned to take up full-time writing.

Koch's first published works were poems which appeared in the Bulletin and Southerly during the 1950s and were described by the editors of The Penguin Book of Australian Verse (1958) as 'powerfully evocative of the Tasmanian landscape.' It was seen as a 'sign of hope' that Tasmania should produce 'two young poets [Koch and Vivian Smith] of such promise simultaneously.' However, it was to the novel that Koch turned and The Boys in the Island, begun while he was still an undergraduate, was published in 1958. Tasmania, its landscape and history, and the concept of a Tasmanian consciousness are important elements in his early work as well as in The Doubleman (1985) and in his book of essays, Crossing the Gap (1987). In his essay 'A Tasmanian Tone', Koch speaks of a 'unique' vision of 'Island people ... a little different from those belonging to a continent.' Koch's recurring preoccupations are the themes of spirituality and cultural identity: his second novel Over the Sea Wall, set in India, and the later novels, set in Indonesia, Vietnam and Ireland, pick up the themes of Australians' engagement with Asia and the 'challenge of ... absorbing the new hemisphere... while retaining their European heritage' (Oxford Companion to Australian Literature). In 1995, Christopher Koch was made an Officer in the Order of Australia for his contribution to literature