A celebrity feud is when two celebrities engage in a public disagreement, often insulting each other or otherwise putting the other person down. Although generally a genuine reaction to some insult or putdown from the other side, the use of celebrity feuds as a source of publicity has not gone unnoticed by management. Celebrity feuds can become extremely emotionally charged, and have lead to the death of one or both of the feuders before.

Feuds are most common in the music industry, and rarest in the television and movie industry.

Some well known feuds include:

• Tupac Shakur and Notorious B.I.G., which lead to the deaths of both men.
• Eminem: Eminem is known for feuding publicly, often using his songs to insult and putdown opponents. He has had personal feuds with Triumph, the Insult Comic Dog (referred to in Ass Like That), Moby, Christina Aguilera (who threatened to sue him), Limp Bizkit, *NSYNC and Mariah Carey. His Shady Records group (consisting of him, Dr. Dre and 50 Cent) also has a running feud with Ja Rule and Murder Inc. Records, although he has called for a ceasefire in one of his recent songs (Like Toy Soldiers), worried that the conflict might escalate to the level of the Tupac and B.I.G. feud.
• Britney Spears and Christina Aguilera, both one-time members of Disney's Mousketeer's Club. The feud began after both began their pop careers at around the same time.
• Lindsay Lohan and Hillary Duff, both trying to carve a niche in the young adult acting-singing-entertaining category, and both romantically linked up with Aaron Carter.
• After the breakup of the Beatles, John Lennon and Paul McCartney feuded for a short time. After Paul referred to John in one of his songs, Lennon wrote How do you sleep? on his Imagine album, accusing McCartney of being a mamma's boy, surrounding himself with phonies, and alleging that his music style was copied from Lennon's. The feud did not last, and the two were friends at the time of Lennon's death in 1980. Subsequently, Paul and John's widow, Yoko Ono, have feuded occasionally. The height of the feud came when a last minute decision on Yoko's side prevented the two from buying back the Beatles' music catalogue, which was bought up by Michael Jackson.
• Vince Neil and Axl Rose: This feud began after Guns N' Roses rhythm guitarist Izzy Stradlin physically assaulted and made disparaging remarks to Sharise, Vince's girlfriend at the time. At the MTV music awards, Vince beat up Stradlin, knocking him unconscious with his fist. Axl Rose then began a press campaign against Neil, saying he would fight him, any time, any place. Vince said "Bring it the fuck on!" Several fight dates were scheduled but each time Axl never showed up. The offer is still intact today.
• Shannen Doherty and Alyssa Milano: Both involved in public fights on the set of Charmed and Doherty later left the show in 2001.