The judge told TV Guide that the Boot Camp and Judges' Homes stages have been dropped in favour of a new "dramatic" aspect to the show.
"There's a middle section to the show that is going to be really dramatic, very tough on us and the contestants, and very high pressure," Cowell said. "You've never seen this before on one of these shows."
He added: "It will look more like the live shows than the Boot Camp, which is completely gone, along with the Judges' Homes. It was the one element of the show I wasn't happy with, and it looked too similar to what everybody else is doing."
However, Cowell - who suggested that fans will "like [The X Factor] more this year" - added that he is not too concerned about shows such as The Voice and American Idol.
"I like competition, I really do," he said. "But there are way too many competition shows, and that's why you've got to constantly evolve. I look at the competition as who is going to do the best with the contestants? Can we do a better job?
"In a year's time you want to be saying, 'This artist is number one all over the world, and it's because they did The X Factor'."
The X Factor USA premieres September 11 on Fox.
Watch a trailer for The X Factor USA below: