"It's been a long couple of years. I just feel it's awesome to be recognized for my music," Bieber, who was up for six awards, told the crowd.
Dressed in a red ensemble, Bieber performed his single "What Do You Mean?" for screaming fans inside the Mediolanum Center in Italy's fashion capital of Milan.
As he picked up his award for best collaboration, Bieber said "it's been a pretty good night." By the time he took the fifth award, for best look, he just said "Wow."
"I don't know what to say, I got these looks from my mamma," Bieber added.He also won the worldwide act: North America category.
Taylor Swift, who led all artists with nine nominations, took just one prize, best song, for "Bad Blood," featuring Kendrick Lamar. Rihanna won best female performer while Nicki Minaj took best hip hop.
One Direction won for best pop group, preventing Bieber from sweeping all the awards for which he was nominated. None of those acts were on hand to accept, and only Minaj sent along a video "thank you."