He was born to Sheila Goldstein and Bob Feldman in Chatsworth, California. Sheila was a Playboy playmate and Bob was a songwriter/record producer who wrote and produced "My Boyfriend's Back" for The Angels, produced "Hang On Sloopy" for The McCoys, and was a member of The Strangeloves who had a #11 hit with "I Want Candy".

Known for playing obnoxious, rebellious young men, Feldman appeared in teen-oriented films including The Goonies (1985). He was often paired with Corey Haim, leading to them to be dubbed The two Coreys. After filming Dream a Little Dream in 1989 Feldman and Haim decided to distance themselves from each other both professionally, but they remain close friends to this day. Feldman also appeared in the comedy The 'burbs that year opposite Tom Hanks and Carrie Fisher.

As an adult Feldman suffered drug problems (heroin and cocaine), and his film career waned and stalled. He was ridiculed for his drug-abuse when he appeared on the Howard Stern Show.

In 1989 Feldman married actress Vanessa Marcil; they divorced in 1993. In 2002 he married Susie Sprague; she gave birth to their first child, a boy named Zen Scott Feldman, on 7 August 2004 in Los Angeles.

In the late 1990s Feldman attempted to launch a music career. In 1999, with Corey Feldman's Truth Movement, he recorded "Still Searching for a Soul". In 2002, he released his first solo album, Former Child Actor, and completed a United States tour promoting the album. He also appeared on "reality" television shows I'm a Celebrity, Get Me Out of Here! and The Surreal Life.

Corey Feldman was a close friend of Michael Jackson. In 2003, when Jackson was accused of child molestation, Corey appeared on Larry King Live (CNN) to express his support, stating he had never seen any misconduct other than kindness on Jackson's part. During the 2005 Jackson molestation trial Feldman revealed in a 20/20 interview how he had been asked to look at nude magazines with Jackson. A tape was subsequently released on Celebrity Justice that featured police interrogating Corey Feldman in 1993 about Michael Jackson. During the hour-long interview, he stated "Nothing ever happened with Michael and me, believe me, if there was something that I'd been hiding for all these years, then I would want nothing more than to bring it out right now". He even volunteered information that he had been molested by someone else but the police did not follow up on Corey's claims of being molested by another person. On June 13, Jackson was acquitted of all molestation charges.

Most recently, Feldman starred in the off-Broadway play Fatal Attraction, a Greek Tragedy, a parody of the seminal 1980s film Fatal Attraction. Feldman played Michael Douglas (the actual name of the character, rather than Dan Gallagher).