Bieber, who only had his first hit last year, beat veteran performers including rapper Eminem, who took home two awards: as top Rap/Hip-Hop male artist, and with top album for "Recovery."
In the country music section Taylor Swift, who won big last year with five awards including overall artist of the year, had to be content with top female artist, while Brad Paisley was chosen top male country artist.
R&B singer Usher was chosen best soul/R&B male artist, and won best soul/R&B album for "Raymond v. Raymond," while Rihanna was named best Soul/R&B female artist.
Bieber, Usher and Rihanna were among musicians who performed at the ceremony, held at LA's Nokia Theater.
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