He was awarded pounds 10,000 for his novel Dependence Day, which has been described as one part Henry James and two parts Sid James and deals with a murder, a Romanian high-jumper and a plot to smuggle drugs from Peru.
It is an unexpected choice for the 11-year-old Betty Trask Award, which was endowed by Miss Trask, a reclusive spinster from Frome in Somerset, for first novels of a romantic or traditional - not experimental - nature by writers under 35.
The work of Mr Newman, who starred with his former partner David Baddiel in the television show Newman and Baddiel in Pieces and was the target for umpteen pairs of teenage girls' knickers when he performed at Wembley, does not at first sight fit that description.
But yesterday he pointed out there were "at least a couple of love stories" in his first book. "The bit in the book that works which is the romantic bit is about Kevin, who is in love with this high-jumper Svetlana and has to get over her when she finishes with him," he explained.
He was less lucid, but more honest, when asked to explain what Dependence Day was about. "I've no idea. There's a coupon at the back of the book which asks readers to return it to me if they know what the plot is," he said. "But I think bits of it are good. The stuff in the first person is good but the rest is filler, which I can't read.
He is working on a film script about a man who, after being released from a mental hospital, develops an obsession with hugging strangers and falls foul of a local gang.
The judges were chaired by Fay Weldon, who last year claimed the Society of Authors had ignored Miss Trask's dying wishes over subject eligibility.