The 'Call My Name' star returns to the judging panel for a fifth year alongside Simon Cowell and newcomers Rita Ora and Nick Grimshaw.
She said: "I haven't been as excited about an X Factor season since I first became a judge.
"The addition of Rita and Grimmy along with some interesting changes we've made to the format has refocused us to do what we do best, finding talent and making stars.
"I cannot wait to get started!"
X Factor returns to ITV this autumn for its 12th series.
As well as a new look judging panel, we will have new hosts as Caroline Flack and Olly Murs are stepping in to replace Dermot O'Leary.
Over on Xtra Factor, we will also have a new host as DJ Sarah-Jane Crawford has left. The identity of her replacement has not been confirmed yet.
X Factor's most shocking moments:
For exclusive competitions and amazing prizes visit Reveal's Facebook page NOW!