Diana Wynyard (January 16, 1906 - May 13, 1964) was a British actress. Born Dorothy Isobel Cox in London, she was a successful stage actress who debuted in film in Rasputin and the Empress in 1932. She was nominated that same year for the Academy Award for Best Actress for Cavalcade.

She appeared in such other films as Gaslight, Tom Brown's Schooldays and Island in the Sun.

She was married to the English film director Sir Carol Reed (1943-1947).

She died from a kidney ailment.