Ryan's Daughter is a 1970 British epic romantic drama film directed by David Lean, written by Robert Bolt and starring Robert Mitchum and Sarah Miles. The film, set between August 1917 and January 1918, tells the story of a married Irish woman who has an affair with a British officer during World War I, despite moral and political opposition from her nationalist neighbours. The supporting cast features John Mills, Christopher Jones, Trevor Howard and Leo McKern. The film is a re-telling of the plot of Gustave Flaubert's 1857 novel Madame Bovary.

The score was written by Maurice Jarre and the movie was photographed in Super Panavision 70 by Freddie Young. In its initial release, Ryan's Daughter was harshly received by critics but was a box office success, grossing nearly $31 million on a budget of $13.3 million, making the film the eighth-highest-grossing picture of 1970. It was nominated for four Academy Awards and won in two categories.