Christa Miller is best known for her television work. She was a cast member of The Drew Carey Show. She acquired a recurring role on Scrubs, and is now a regular cast member.

She was born in New York City, the daughter of 1960s model Bonnie Trompeter. Miller was a model as a child, appearing in a Wonder Bread commercial when she was six months old, posing at three for Francesco Scavullo in an Ivory soap advertisement, and photographed for the cover of Redbook magazine. Her days as a child model were curtailed after an operation for a benign bone tumor. After attending Convent of the Sacred Heart, Miller returned briefly to modeling, but soon took acting lessons, abandoning modeling for good when she moved to Los Angeles, California, in 1990.

Her first role on television was in Kate & Allie, which starred her similar-looking aunt, Susan Saint James. She was also in episodes of Northern Exposure, Seinfeld, Fresh Prince of Bel Air and Party of Five. She had a major role on The Drew Carey Show from 1995 to 2002 playing Kate, and was the voice of Cleopatra in her husband's short-lived animated show Clone High.

In 2001, her husband, writer-producer Bill Lawrence, conceived a new show called Scrubs and Miller was given a recurring guest role as surly Dr. Cox's (John C. McGinley) equally bitter ex-wife Jordan Sullivan. Her role has increasingly become a major part of the show.

Christa Miller also appeared twice in Seinfeld, as two different characters; one, the boss of a potential employer of George, and the other, a woman whom George unsuccessfully dates.

Miller has three children with Bill Lawrence: Charlotte Sarah, born in 2000; William Stoddard, born in 2003; and Henry Vanduzer, born in October 2006.

Miller was on the cover of the first issue of the American edition of Maxim magazine.

Despite sharing the same last name, the boy who plays Jordan & Cox's son (Baby Jack) on Scrubs is not related to Miller.

Christa got pregnant in real-life during shooting the fifth season of Scrubs. It was this which resulted in the storyline Dr. Cox and Jordan Sullivan having their second child. Due to this, and the fact that characters Turk and Carla were also trying for a baby, the writers decided to write a baby theme for the season, and make JD's, the main character, girlfriend pregnant as well.