The fourth Harry Potter film will be shown on giant Imax cinemas as well as normal ones when it's released.
Harry Potter and the Goblet of Fire comes out on 18 November in the UK and the US, and fans can choose which type of screen they want to watch it on.
The Prisoner of Azkaban was shown on Imax cinemas, but after it came out on regular screens. There are 240 Imax cinemas across the world.
Imax screens are huge - they are eight storeys high and can show in 3-D.
Imax has made lots of deals with movie companies to transfer blockbusters onto their giant screens in recent years. Spider-Man 2, Lord of the Rings and the forthcoming Batman Begins have all been converted.
But for Potter fans who can't wait til November, the sixth book, Harry Potter and the Half-Blood Prince, is out on 16 July.