The group, which called itself the Jackson Jive, sang the Jackson 5 song, "Can You Feel It," on Wednesday's special edition of the variety program on which Connick was a guest judge, CNN said.
"If they turned up looking like that in the United States, hey, hey, there's no more show," the U.S. news network quoted Connick as saying with a frown about the performance.
"It didn't occur to me until later -- I think we may have offended you with that and I deeply apologize on behalf of all of us," the show's host, Daryl Somers, told Connick. "Because I know, your countrymen, it's an insult to have a blackface routine."
CNN said Connick replied by saying he wouldn't have appeared on the show had he known about the act beforehand.
Copyright 2009 by United Press International.