Mr. Justice Raffles is a 1909 novel written by E.W. Hornung. It featured his popular character A. J. Raffles a well-known cricketer and gentleman thief. It was the fourth and last in his four Raffles books which had begun with The Amateur Cracksman in 1899. The novel was published in the UK by Smith, Elder & Co., London, and in the US by Scribner's, New York.

Ernest William Hornung was an English author and poet known for writing the A. J. Raffles series of stories about a gentleman thief in late 19th-century London. Hornung was educated at Uppingham School; as a result of poor health he left the school in December 1883 to travel to Sydney, where he stayed for two years. He drew on his Australian experiences as a background when he began writing, initially short stories and later novels.