The actress - who portrayed Princess Leia in the first three movies of the George Lucas-directed sci-fi franchise - snorted the drug with others on the set of the 1980 film, despite not being a fan of the substance.
She said: "We did cocaine on the set of `Empire`, in the ice planet.
"I didn`t even like coke that much, it was just a case of getting on whatever train I needed to get high."
Carrie only looked to get help when she saw her `Blues Brothers` co-star John Belushi die from a drugs overdose in 1982.
She told AAP: "Slowly I realised I was doing a bit more drugs than other people and losing my choice in the matter.
"If I`d been addicted to booze I`d be dead now, because you just go out and get it."
Carrie may be best known for her role in the `Star Wars` movies, but she has since starred in a number of successful projects, including 2003`s `Charlie`s Angels: Full Throttle` in and 2008`s `The Women` alongside Eva Mendes and Jada Pinkett Smith.