Steve Toltz (born 1972 in Sydney) is an Australian novelist. Toltz graduated from the University of Newcastle, New South Wales, in 1994. Prior to his literary career, he lived in Montreal, Vancouver, New York, Barcelona, and Paris, variously working as a cameraman, telemarketer, security guard, private investigator, English teacher, and screenwriter.

A Fraction of the Whole, his first novel, was released in 2008 to widespread critical acclaim. It is a comic novel which tells the history of a family of Australian outcasts. The narration of the novel alternates between Jasper Dean, a philosophical, idealistic boy, who grows up throughout the novel, and his father, Martin Dean, a philosopher and shut-in described at the start of the novel as "the most hated man in Australia".