Isaac Mizrahi was born in Brooklyn, New York. He studied acting at the High School of Performing Arts and fashion at the Parsons School of Design.
In 1987 Mizrahi established his first clothing business. He received three CFDA Designer of the Year awards. In 2003, he launched a successful collection of women's sportswear and accessories at Target stores, while simultaneously debuting a couture line exclusively for Bergdorf Goodman. He launched a successful collection of home furnishings for Target in February 2005.
Mizrahi has designed costumes for movies, theatre, dance and opera in collaboration with Mark Morris, Twyla Tharp, Mikhail Baryshnikov and The Roundabout Theatre Company. In 2002 Mizrahi received the Drama Desk Award for his costume design in The Women.
In 1995 Mizrahi was the subject of the highly acclaimed documentary Unzipped. The film was screened internationally at the Cannes and Venice Film Festivals, distributed nationally by Miramax and awarded the 1995 Audience Award for Documentaries at the Sundance Film Festival. In 1996 Mizrahi received a special CFDA Award for bringing the fashion world to cinema.
In 1997 Mizrahi wrote a series of comic books entitled The Adventures of Sandee the Supermodel. In 1999 Mizrahi appeared off-Broadway in a one man show, Les Mizrahi, produced by the Drama Department and, from 2001 to 2003, hosted his own televisions show, the "The Isaac Mizrahi Show" on the Oxygen Network.
In 2005 Mizrahi wrote and directed four short films entitled Supermodelhero which debuted online in April 2005.
Mizrahi has also worked as the costume designer for three Broadway revivals, including two plays, The Women in 2001 and Barefoot in the Park in 2006, and one operetta Threepenny Opera in 2006. For his work on The Women, he won the 2002 Drama Desk Award for Outstanding Costume Design. Mizrahi was also costume designer for the Metropolitan Opera's 2008 production of Orfeo ed Euridice, directed by Mark Morris, continuing as a longtime collaborator of Morris' in a partnership stretching as far back as 1997, when Mizrahi created costumes for Morris' film project with Yo-Yo Ma, Falling Down Stairs from Ma's Inspired by Bach series.