The hip-hop legends - consisting of Joseph 'Run' Simmons and Darryl 'DMC' McDaniels - will reunite for this year's Fun Fun Fun Fest, which takes place from November 2 to November 4 in Austin, Texas.
The pair have not played together since the murder of fellow member Jason 'Jam Master Jay' Mizell in 2002.
Since his unresolved killing, the relationship between Simmons and McDaniels has been strained, and they have turned down opportunities to reform in the past.
However, to mark the tenth anniversary of Mizell's death, they will headline the Fun Fun Fun main stage, and will donate a portion of their appearance fee to the JMJ Foundation for Music.
[Run-DMC photographed in February 2002, before the death of Jam Master Jay]
The charity provides access to the arts and music for children and young adults.
Run-DMC had dismissed rumours of a reunion back in April 2010.
The pair will appear in the upcoming documentary The Art of Rap, which charts the history of rap and hip-hop music. It will be released on July 20.
Watch the video for Run-DMC's 'It's Tricky' below: