Lena Maria Jonna Olin (born 22 March 1955) is a Swedish actress. She has received nominations for an Academy Award, a Golden Globe Award, a BAFTA Award, and a Primetime Emmy Award.

Mentored by filmmaker Ingmar Bergman, she made her screen debut with a small role in his film Face to Face (1976). After graduating from the drama school, Olin joined the Royal Dramatic Theatre, followed by roles in Bergman's films Fanny and Alexander (1982) and After the Rehearsal (1984). She made her international breakthrough with a role of a free-spirited artist in The Unbearable Lightness of Being (1988), which earned her a nomination for the Golden Globe Award for Best Supporting Actress – Motion Picture.