The author of the novel 'Rich Man, Poor Man' is Irwin Shaw. He was an American playwright, screenwriter, novelist, and short-story author whose works were widely popular during the mid-20th century. His most famous work, 'Rich Man, Poor Man, ' was published in 1970 and was adapted into a television miniseries in 1976. The novel follows the lives of two brothers, Rudy Jordache and Tom Jordache, as they navigate their way through life in the 1940s and 1950s. Shaw's other works include 'The Young Lions, ' 'Bury the Dead, ' and 'Nightwork.'