Ruth Ryan Langan (born December 12, 1937 in Detroit) was an American writer of romance novels.
She is a New York Times Bestselling author of over one hundred novels, both historical and contemporary under the penname Ruth Langan.
She also writes contemporary Western romantic suspense for Grand Central Publishing, as well as some novellas for Jove under the pseudonym R. C. Ryan.
Ruth Ryan Langan began her writing career in secret.
When Langan's husband was told of her hobby, he bought her an electric typewriter "because 'writers need tools'".