It was a part that catapulted her into the limelight as one of the most famous faces on the planet.
But the fame brought a price and her personal life was dogged by failed relationships, mental health issues, and drug and alcohol abuse.
She later turned to writing before returning to Star Wars in the 2015 film, The Force Awakens.
Carrie Frances Fisher was born on Oct 21 1956, the daughter of Academy Award-nominated actress Debbie Reynolds and pop singer Eddie Fisher.
Fisher's parents divorced two years later, after her father had an affair with one of Reynolds' closest friends, Elizabeth Taylor. Her father and Taylor later married.
She was a self-confessed bookworm as a child reading poetry and classical literature. Her high school education was disrupted by the lure of the stage when she appeared in the musical Irene alongside her mother, and she never graduated.
She moved to London where she enrolled in the Central School of Speech and Drama before returning to the US and attending the Sarah Lawrence arts college near New York.
Fisher made her big screen debut in the film Shampoo (1975), alongside Goldie Hawn, Warren Beatty and Julie Christie, but it would be another two years until she got her big break in Star Wars.
She told the Daily Mail  in 2011 that when she got the part in a "little science-fiction film", she just thought of it as a bit of fun. "But then Star Wars, this goofy, little three-month hang-out with robots did something unexpected," she said.
"It exploded across the firmament of pop culture, taking all of us along with it. It tricked me into becoming a star all on my own."
Fisher's memoir, The Princess Diarist, released in 2016, revealed for the first time that the then 19-year-old actress had an affair with co-star Harrison Ford, who was then married to Mary Marquardt. The affair ended after three months.
In the memoir, she wrote: "I don't remember much about things like the order we shot scenes in, or who I got to know well first.
"Nor did anyone mention that one day I would be called upon to remember any of this long-ago experience."
In 1980 she reappeared in The Empire Strikes Back and, three years later in the third Star Wars film, Return of the Jedi.
She married singer Paul Simon in 1983. The pair had been in a relationship for five years, but they divorced just a year later.
Fisher had other roles during the decade, including in Woody Allen's Hannah and Her Sisters (1986) and When Harry Met Sally (1989), but none had the same impact as the Star Wars franchise.
She also made a number of stage appearances during and after the filming of Star Wars.
Having managed to kick drugs and alcohol, she was rushed to hospital in 1985 after accidentally taking an overdose of sleeping pills and prescription drugs.
The episode formed the basis for her first novel, the semi-autobiographical Postcards from the Edge, in which she satirised her own dependence on drugs and the sometimes difficult relationship she had with her mother.
Three years later Fisher adapted it into a screenplay, and it was made into a film starring Meryl Streep, Shirley MacLaine, and Dennis Quaid.
There were three further novels, Surrender the Pink, Delusions of Grandma and The Best Awful.
She had a number of minor roles in various films but she found herself unable to recapture the profile that Star Wars had given her.
Fisher - who had bipolar disorder - also wrote and frequently talked in public about her years of drug addiction and mental illness.
In 2001, she told Psychology Today: "Drugs made me feel normal. They contained me."
She also featured in a 2006 BBC television documentary Stephen Fry: The Secret Life of the Manic Depressive.
By the turn of the century she had made something of a reputation as a script doctor, revising and polishing screenplays by other writers. Among the films she lists as having worked on were Hook, Sister Act and Lethal Weapon 3.
In 2007, she wrote and performed her autobiographical one-woman show Wishful Drinking, which was released as a book the next year.
It was confirmed in 2013 that she would reprise her role as Leia in Star Wars VII which screened in 2015 as Star Wars - The Force Awakens. She appeared alongside original cast members Harrison Ford and Mark Hamill.
Billed as a sequel to The Return of the Jedi, the film became the highest grossing episode of the Star Wars franchise. Her character leads the resistance against the First Order, as she continues to seek the missing Luke. She won a Saturn Award in 2016 for Best Supporting Actress.
Days after the release of the film it was announced that Fisher would return in Star Wars VIII in 2017.
As well as her marriage to Paul Simon, Fisher also had a three-year relationship with talent agent Bryan Lourd, which resulted in the birth of her daughter, Billie Lourd.
Carrie Fisher's fame as an actress rested on just one role, but it was a role in one of the best known and most successful film franchises in cinema history.
She was remarkably frank about the personal difficulties she had fought and overcome.
"There's a part of me that gets surprised when people think I am brave to talk about what I've gone through," she once said. "I was brave to last through it."
Carrie Fisher's acting career was dominated by her role as Princess Leia Organa in the Star Wars franchise.