"I've always wanted Paula and have always been very vocal about that," said Cowell in a statement regarding Abdul's new judging duties. "You just have to get that chemistry, and she's right. I've never found anyone better than her," he added.
The panel will also include Antonio L.A. Reid, who was previously the chairman of Island Def Jam Records, and British singer Cheryl Cole.
Based on the successful U.K. series, The X Factor debuts next fall on Fox.