The SOLARIS star has accused Cowell of only appearing on the talent search show so he can seduce the female contestants.
He also slammed the sharp-tongued Brit for the often-harsh comments he makes about the wannabe pop stars' performances. Clooney ranted, "Cowell is not helping them. He is doing it to show how interesting he can be.
"All he is trying to do is get laid. He is quite open about it and I am like, 'Is that your best way of getting laid?'
"Guys like that don't last very long."
But Cowell has struck back at former ER star Clooney, stating, "He spent five years getting dressed up as a doctor and then went on to wear a BATMAN suit.
"Attractive women do come on to me. I'm not going to protest about it."
But Cowell does agree with Clooney on one criticism.
The music mogul admits, "I'm not expecting to last."