Castle On The Hill Ed Sheeran
Jessie J will join Tulisa at the judges' houses to help pick the finalists.
When a fan tweeted the 'Who's Laughing Now' singer to ask about X Factor rumours, Jessie didn't deny she'll be appearing on the show.
";) yeeaahh man!" she said in response to a tweet saying, "WOW @jessiejofficial appearing on UK XFactor as guest mentor with Tulisa?!?"
Reports say Jessie J will squeeze in the mentoring job with Tulisa at the same time as her UK Heartbeat tour which kicks off next month.
Meanwhile Jessie has been taking tips from Katy Perry after the pair got pally at the MTV VMAs, where Katy told Jessie to "get that foot fixed before the tour".