The One That Got Away singer was praised for landing five number one songs and six top five hits on the Billboard Top 100 over the course of the year, matching records set by the likes of Michael Jackson in the process.
She told MTV News: 'To be Artist of the Year, a whole 365 days, that's pretty cool.
'I wasn't really allowed to watch MTV growing up, so this feels really validating.
'I've had a fantastic year, a great tour and a great run, and you guys have been so a part of it and such a big reason why. I really appreciate it.'
The 27-year-old also embarked on the 124-date California Dreams tour which launched in January and has seen her perform across five different continents.