Speaking on Radio 1, Cheryl insisted she was still a fan of the series but bluntly ruled out any idea that she would return.
The Girls Aloud star, who won the series in 2008 and 2009 with Alexandra Burke and Joe McElderry respectively, was quizzed by Ferne Cotton over the ITV1 series.
Asked if she would ever return to the panel, Cheryl replied simply "No."
Cheryl, who starts her first headlining tour next month, also revealed she had yet to watch any of this year's series as she had been rehearsing in America.
But the 29-year-old added: "I’ve watched some of it last year, and I felt like it was a different show."
There's little denying Cheryl's impact on the ratings, with viewing figures having soared since her first appearance in 2008 and declined since she, Simon Cowell and Dannii Minogue all quit the show in 2010.
The X Factor launched with over 11 million viewers for its first audition episode two years ago, compared to 8.7 million this year.
And in more bad news for show bosses, the ratings have continued fall since.
Saturday night's latest installment was seen by 8.57 million viewers, despite better weather which had been blamed for the low launch night ratings.