The Take That singer invited the ex-judge to help him during his Judges' Houses round in 2012, and he has said he would have her back again "in a heartbeat" this year.
Asked if he had approached the former Girls Aloud singer to help him pick his finalists again, Gary told us: "I don't know yet, but who knows? I love Cheryl, love Cheryl.
"I always ask her to do things, we did the Jubilee together, so I would have her back in a heartbeat."
Speaking at the first round of arena auditions at Wembley on Monday, he said: "I liked Tulisa, we had two good years and she always gave a lot of time to her acts. But she's gone and I think Mrs O coming back is a good thing for the show."
Gary has also been at the centre of reports he's set to quit 'X Factor' following this year's series to focus on Take That's new album and tour in 2014.
However, he played down the rumours when quizzed by reporters on the red carpet, saying: "It's far too early to be thinking about next year. I'm focused on this year."