The studio audience at the taping of the show went wild as the Culture Club star made the admission, which stopped the show as crew members raced to the singer to discuss his comments, according to The Sun.
The confession was made as the 54 year old and fellow judges Paloma Faith, will.i.am and Ricky Wilson chatted about the most famous people they had collaborated with.
Boy George said, "I have duetted with some of the greatest soul singers in history including Luther Vandross and Smokey Robinson", prompting Paloma to respond, "Well OK, if we're throwing big soul names out there, I've performed with Prince."
Without missing a beat, George chuckled, "Forget that, darling, I've slept with Prince!"
A source on set says, "Production staff had to come up on stage and speak to them. After that, Boy George started backtracking, saying he hadn't really slept with Prince and that in reality, he just had his poster on his wall. But as far as the crowd were concerned the cat was already out of the bag."
Boy George recently replaced Sir Tom Jones on The Voice.
It is not known if his Prince comments or the fuss surrounding them will feature on the talent show when it returns to TV in the U.K. in January (16).