The footage was first released to The National Enquirer, and The Daily Mail published the video on its website earlier this week.
Jolie is arguing that the publication of the video is a gross violation of her privacy, according to The Times.
After The Daily Mail posted the video, the newspaper published another article touting how Jolie has gone from "heroin to heroine."
The video reportedly shows Jolie in a New York City apartment high on heroin as she talks to her father on the phone about family problems. Her alleged drug dealer says he shot the video with Jolie's consent in 1999.
The dealer claims that he supplied Jolie with drugs - including heroin and cocaine - two to three times a week during that time.
It's unclear whether Jolie plans to take legal action against the Enquirer as well.
In interviews, Jolie has previously alluded to a "dark time" in her life and has said that she's lucky to be alive. The Huffington Post points out that in 1996, Jolie said in an interview that she has "done just about every drug possible: cocaine, ecstasy, LSD, and my favorite, heroin." Industry sources say photos that apparently show Jolie high on drugs have been floating around for years.
The alleged heroin video is said to be taken around the time Jolie was promoting the movie "Girl, Interrupted." She won an Oscar for her role in the film.