Taylor made AMA history by taking home Artist of the Year for the third year in a row; she also scooped up three other awards.
"I'm 23 and I have no idea what's going to happen to me in my life," she said in her acceptance speech. "But if [the fans] decided on something as wonderful as this [award], then we're pretty much in it together."
The pretty blonde also won Favourite Female Pop/Rock Artist, Female Country Artist and Country Album for her 2012 record Red, which featured songs about love and heartbreak.
In the awards, which are voted for by fans, British heartthrobs One Direction snatched up the title of Best Pop/Rock Album for Take Me Home. The five-strong boy band also won Favourite Pop/Rock group.
Justin Timblerlake won three gongs, including Favourite Male pop/Rock Artist, while Rihanna accepted the first-ever Icon Award at the prestigious Los Angeles music event, which brought some of pop music's biggest names together.
The Barbados-born singer was lucky enough to be presented the award by her mum, Monica Braithwaite, following a video commemoration from Jay Z and a video montage showing her career highlights.
"I know the journey and your career has not always been an easy one," her mum said. "But tonight I applaud and admire you for being so strong and so positive and so humble and so focused. . . I'm so blessed to be part of this historic moment."
Wearing a long black dress with a plunging neckline, diamond-studded hair adornments and silver choker, Rihanna then performed her song Diamonds, from her most recent full-length album, Unapologetic.
Other performances were delivered by Miley Cyrus, who shed an elegant white ensemble for a skimpy cat-themed outfit to sing Wrecking ball, Katy Perry, One Direction, Lady Gaga and R. Kelly and Jennifer Lopez.