Pictures: Lady Gaga's out of this world at MTV Awards
Check out Lady Gaga's latest creations and who won what at the 2011 MTV Europe Music Awards in Belfast.
And Bruno Mars was celebrating a double success, winning best new act and the "push" artist award, which goes to an act who's been promoted by MTV as an up-and-coming star.
She later told reporters her stage outfits were made from paper, adding: "It was inspired by the idea of the paper moon because there was a moon on the stage tonight."
Lady Gaga was the big winner at the 18th MTV Europe Music Awards. She took home four trophies, including best song and best video for her single Born This Way. She also performed her latest song, Marry The Night.
Lady Gaga didn't disappoint fans of her outrageous outfits either...
Selena Gomez gave Lady Gaga a run for her money when it came to costume changes. She showcased eight different outfits while hosting the two-hour show in Belfast.
As well as performing her hit single Price Tag, Jessie J introduced a video tribute to Amy Winehouse, featuring fans' memories of the singer, who died in July.
Katy Perry had plenty to smile about too - she was named best live act.
When Justin Bieber picked up the awards for best pop and best male, his girlfriend Selena Gomez commented to Katy Perry: "He's cute, isn't he?"