The I kissed A Girl star, who was recently a guest judge on the show in Dannii Minogue's temporary absence, said: "I adore Cheryl, she's amazing."
She also added that if she weren't with British comedian Russell Brand, she'd want to be in a relationship with the Girls Aloud star.
"I'm very happy with my own English stud but if I wasn't with him I'd be trying to date Cheryl," she added.
"Nobody should be as beautiful as she is. I know people get turned on by Simon's power but if I was single I'd rather sleep with Cheryl than Simon."
Perry's debut single, I Kissed A Girl, topped the charts in more than 30 countries, including America, Australia, Canada, Ireland and the UK.
