An 18-year-old has won the top prize at the
American Music Awards.
Canadian Justin Bieber won artist of the year Sunday in Los Angeles at the 40th anniversary show, beating out Rihanna, Maroon 5, Drake, and Katy Perry.
The teenager said when he accepted his award that it was "hard growing up with everyone watching me" and he thanked his mother for "always believing in me."
Bieber also won in the pop/rock album category for this album
Believe, and he won the pop/rock male artist award.
Canadian Carly Rae Jepsen won favorite new artist.
New mom Adele from Britain took the top prize in the adult contemporary category.
Taylor Swift won her fifth consecutive award for favorite country female artist, while Luke Bryan won the country male prize.
Usher kicked off the three-hour televised show on ABC with green laser lights beaming onstage as he performed a medley of songs. Usher also took home the prize for best soul/R&B artist.
American Music Award nominees are selected based on sales and airplay, and fans chose the winners by voting online.
Photo Gallery
Justin Bieber accepts the award for artist of the year as his mom Pattie Malette looks on at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Stevie Wonder and the Rickey Minor Band perform a tribute to Dick Clark at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Stevie Wonder and the Rickey Minor Band perform “Master Blaster”, “My Cherie Amour” and “Sir Duke” as a tribute to Dick Clark at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Psy performs at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
MC Hammer, left, dances as PSY performs “Gangnam Style” at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Carrie Underwood performs at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Lady Antebellum accepts the award for favorite band, duo or group - country at the 40th Anniversary American Music Awards on Nov. 18, 2012
Christina Aguilera, left, and Pitbull perform at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Nicki Minaj accepts the award for favorite artist - rap/hip-hop at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Carly Rae Jepsen poses backstage with the Old Navy new artist of the year award at the 40th Anniversary American Music Awards on Nov. 18, 2012, in Los Angeles.
Justin Bieber accepts the award for favorite male artist - pop/rock at the 40th Annual American Music Awards Nov. 18, 2012, in Los Angeles.