The music channel will be taking over the city of Belfast on Nov. 6 for its annual ceremony, and for the first time the MTV Europe awards will be held in three different locations.
Gaga and Mars will join Coldplay, Jessie J and LMFAO in performing at the Odyssey Arena. The Red Hot Chili Peppers will be playing at Ulster Hall, while Snow Patrol and Jason Derulo will be on stage at City Hall.
The show is being hosted by actress/singer Selena Gomez.
Gaga leads the way with six MTV Europe music award nominations, while Mars and Katy Perry have four each.