Kazan was born Lanie Levine in Brooklyn, New York City, the daughter of a Russian Ashkenazi Jewish father who worked as a bookie and a Turkish Sephardic Jewish mother, Carole, whom Kazan has described as "neurotic, fragile and artistic". She was married to Peter Daniels from 1971, however, she revealed that she was divorced. She has one daughter named Jennifer from that marriage, and is a grandmother herself. She serves on the boards of the Young Musicians' Foundation, AIDS Project LA, and B'nai Brith. She is a graduate of Hofstra University.
Kazan suffers from deep vein thrombosis, and has dedicated time to educating the public about the condition.
Lainie made her Broadway debut in The Happiest Girl in the World in 1961 followed by Bravo Giovanni (1962). She served as understudy to Barbra Streisand in Funny Girl, finally getting to go on 18 months into the run when the star was felled by a serious throat problem. Coincidentally, both had attended the same high school, Erasmus Hall High School in Brooklyn, New York. Kazan's mother alerted the press and, encourage by rave reviews for her performance, she quit the show and set out to establish herself in a singing career.
As her popularity increased, Kazan posed nude for a spread in the October 1970 issue of Playboy, which was re-used in Pocket Playboy #4, issued in 1974. Her appearance in the magazine opened the door for her to headline and operate two different Playboy Jazz Clubs, both under Hugh Hefner's overview, which she called Lainie's Lounge East and West on opposite coasts, one in Los Angeles and the other in Manhattan. Her playboy photographs also inspired the look of Jack Kirby's DC Comics superheroine Big Barda.
Kazan appeared in numerous supper clubs across the country, and she guested on Dean Martin's variety series 26 times. Other television work includes a recurring role as Aunt Frieda on the Fran Drescher sitcom The Nanny and as Kirstie Alley's mother on Veronica's Closet, and guest shots on St. Elsewhere (resulting in an Emmy nomination), The Paper Chase, Touched by an Angel and Will & Grace. She was also featured in My Big Fat Greek Life, a short-lived series based on the Nia Vardalos hit film My Big Fat Greek Wedding, in which she had also starred alongside Vardalos. She appeared in a scene as the mother of Adam Sandler's character in I Now Pronounce You Chuck and Larry, but it was deleted in the feature film. It is, however, included in the special features on disc. Prior to this film, she had appeared with its co-star Kevin James in three episodes of his The King of Queens TV series as the once-renowned signer Ava St. Clair.
Kazan returned to Broadway to recreate her film role for the musical adaptation of My Favourite Year, earning a Tony Award nomination for her performance. She completed a stint in The Vagina Monologues. She has also appeared in regional productions of A Little Night Music, Man of La Mancha, Gypsy, Who's Afraid of Virginia Woolf?, Hello, Dolly!, and Fiddler on the Roof, among others. In 1984, she made a guest appearance on the Faerie Tale Theatre episode "Pinocchio" as Sophia the Blue Fairy.
In recent years, Kazan has performed on concert stages and in Las Vegas and Atlantic City showrooms.
She appeared in an episode of Ugly Betty, playing the mother of Bobby, who was soon to become the central character's brother in law. Thus, her character was soon to become the mother in law of the central character.
On August 17, 2010, The Hollywood Reporter announcer that Kazan would join the cast of Desperate Housewives for Season 7. She played the role of a self-employed business owner and neighbour to Susan.
- Dayton's Devils (1968)
- Lady in Cement (1968)
- Romance of a Horsethief (1971)
- One from the Heart (1982)
- My Favourite Year (1982)
- Lust in the Dust (1985)
- The Journey of Natty Gann (1985)
- The Delta Force (1986)
- Medium Rare (1987)
- Harry and the Hendersons (1987)
- Married to the Mob (1988)
- Beaches (1988)
- Eternity (1989)
- Out of the Dark (1989)
- 29th Street (1991)
- I Don't Buy Kisses Anymore (1992)
- The Cemetry Club (1993)
- Movies Money Murder (1996)
- Love Is All There Is (1996)
- The Associate (1996)
- Allie & Me (1997)
- The Big Hit (1998)
- Permanent Midnight (1998)
- The Unknown Cyclist (1998)
- Kimberly (1999)
- Mike & Spike Movie (1999)
- The Crew (2000)
- The Dress Code (2000)
- What's Cooking? (2000)
- My Big Fat Greek Wedding (2002)
- Eight Crazy Nights (2002) (voice)
- Returning Lilly (2002)
- Broadway: The Golden Age, by the Legends Who Were There (2003) (documentary)
- A Good Night to Die (2003)
- Gigli (2003)
- Red Riding Hood (2004)
- The Engagement Ring (2005)
- Whiskey School (2005)
- Bratz: The Movie (2007)
- Beau Jest (2007)
- You Don't Mess with the Zohan (2008)
- Oy Vey! My Son Is Gay!! (2009)
- Expecting Mary (2010)
- Desperate Housewives (2010)