Leifer was born in East Williston, New York, to an Ashkenazi Jewish family, the daughter of Anna, a psychologist, and Seymour Leifer, an optometrist. Carol Leifer Biography (1956-)

While studying for a theater degree at Binghamton University, Leifer accompanied her then boyfriend Paul Reiser to a comedy club to see him perform at the open mic night at Catch A Rising Star. Later she tried performing at New York's Comic Strip and was introduced by emcee Jerry Seinfeld. All three have had successful television and comedy careers.

Leifer is a stand-up comedian, writer, producer and actor and has been involved in such television shows as Seinfeld, It's Like, You Know..., Alright Already, and The Larry Sanders Show. With Mitchell Hurwitz, she is the creator of the short-lived The Ellen Show (2001). In 1988, she had her own special on Cinemax titled Carol Doesn't Leifer Anymore, which was produced by David Letterman. This was shortly followed several more specials, tiled Carol Leifer Comedy Cruise (1989), Really Big Show (1990), and Gaudy, Baudy, and Blue (1992). She was a writer on Saturday Night Live during the 1985/1986 season.

She has performed on Late Night With David Letterman 25 times, but has only been on Dave's show once since 1992. Carol has also appeared on The Tonight Show Starring Johnny Carson, Dr. Katz, Politically Incorrect with Bill Maher, Hollywood Squares, Late Night with Conan O'Brien, and The Tonight Show with Jay Leno. Her hosting duties have included four seasons of A&E's Caroline's Comedy Hour, as well as guest stints on Talk Soup and Later.

Carol has written for the Academy Awards for most of the 21st century.

Leifer starred in, created and executive-produced the WB sitcom Alright Already. called one of the "10 Best New Shows of the New Season" by the Los Angeles Times and The Washington Post. Despite good reviews, the show only ran one season.

Her stand-up experience includes opening for Jerry Seinfeld and Frank Sinatra. Sinatra praised Leifer as "one funny broad!" and "I wish my mother had been that funny - I wouldn't have had to work so hard." She continues working the stand-up circuit and is reportedly writing an original picture for Dreamworks. Additionally, Leifer is a writer and co-executive producer on the CBS sitcom Rules of Engagement.

In September 2007, Leifer won an auction for the handwritten notes used by Michael Vick during his apology for his role in dogfighting.

Leifer is currently in a committed relationship with Lori Wolf, who works in commercial real estate. They share a $3.2-million, home in the Santa Monica Hills. They have one son, named Bruno Leifer-Wolf, who was born January 17, 2007.

Her first book of humorous essays, entitled When You Lie About Your Age, The Terrorists Win was released on March 10, 2009. In it, she discusses the moment she discovered she might be gay and how her life has changed for the better.

Carol began filming as a contestant for the 3rd season of Celebrity Apprentice in October 2009. Shalom Life reported that she had been the first to be eliminated on the premier episode which aired on March 14th, 2010.

Leifer joined the Seinfeld writing staff during its fifth season, and wrote six episodes for the show between then and its seventh season. She has been dubbed "the real Elaine," having the character being partially based on her. Her episodes, listed chronologically, are:

Season five

• "The Lip Reader"
• "The Hamptons" (co-written with Peter Mehlman)

Season six

• "The Secretary" (co-written with Marjorie Gross)
• "The Beard"
• "The Understudy" (co-written with Marjorie Gross)

Season seven

• "The Rye"