The X Factor judge had reportedly fallen out with the music mogul over Christopher Maloney, the contestant that is mentored by Barlow on the show.
According to reports last week, Cowell said that he wanted Maloney out of the competition this year.
It was also reported that Cowell thinks it would be a "disaster" if the 34-year-old Liverpudlian were to win the show.
Speaking on The Xtra Factor tonight (November 3), Barlow was asked whether it was true whether Cowell and Barlow had come to blows over the contestant.
Barlow said: "I don't know of any clash, I don't read newspapers."
He continued, saying that "there's been no clash", adding: "But whether something's been said backstage, I'm not sure."
Photo gallery - The X Factor number ones week: