Didi Conn (born July 13, 1951) is an American film, stage and television actress.

Conn was born Edith Bernstein in Brooklyn, New York, the daughter of a clinical psychologist. She attended Midwood High School, and is married to composer David Shire; her brother is opera singer Richard Bernstein.

Conn's notable roles include:

• "Laurie Robinson" You Light Up My Life 1977
• "Frenchy" in the feature films
• Grease (1978, starring John Travolta and Olivia Newton-John)
• Grease 2 (1982, starring Michelle Pfeiffer)
• "Denise Stevens Downey" on the TV show Benson (1981-85, with Robert Guillaume)
• "Stacy Jones" on the children's TV show Shining Time Station (1989-93).

Conn also provided the voice for Raggedy Ann in the 1977 animated feature, Raggedy Ann & Andy: A Musical Adventure, directed by Richard Williams. Her "childlike" voice is one of her trademarks. Conn also appeared as a panelist few times on the 1970s game show Match Game.

She has a son, with David Shire, born in 1992.

Mother of a son named Danny.

Was considered for the role of Olive Oyl in Popeye (1980)

She wanted to read the role of Rizzo at her Grease (1978) audition, but the producers decided that she was exactly right to play the part of Frenchy.

Younger brother is bass-baritone opera star Richard Bernstein (II).

She once attended a school play of "Grease" at Nyack Middle School (in the play, "Danny" was played by "Freaks and Geeks" (1999) star John Francis Daley). Didi signed autographs for the cast, crew and audience.

Studied mime with Tony Montanaro in the first year of his Celebration Mime Theatre.

In 2003 it was reported that she was a driving force behind a planned third Grease film. She featured in the first two films as Frenchie.