Dianne Evelyn Wiest (; born March 28, 1948) is an American actress. She has won two Academy Awards for Best Supporting Actress for 1986's Hannah and Her Sisters and 1994's Bullets Over Broadway (both directed by Woody Allen), one Golden Globe Award for Bullets Over Broadway, the 1997 Primetime Emmy Award for Outstanding Guest Actress in a Drama Series for Road to Avonlea, and the 2008 Primetime Emmy Award for Outstanding Supporting Actress in a Drama Series for In Treatment. In addition, she was nominated for an Academy Award for 1989's Parenthood.

Other film appearances by Wiest include Footloose (1984), Woody Allen's The Purple Rose of Cairo (1985), Radio Days (1987), and September (1987), The Lost Boys (1987), Bright Lights, Big City (1988), Edward Scissorhands (1990), Little Man Tate (1991), The Birdcage (1996), Practical Magic (1998), Dan in Real Life (2007), Synecdoche, New York (2008), Rabbit Hole (2010), The Mule (2018), Let Them All Talk (2020), and I Care a Lot (2020). She also appeared in the television series Law & Order (2000–2002), and the CBS comedy Life in Pieces (2015–2019).