The X Factor creator admitted that he loves her "naughty side" and insisted she should be given a star on the Hollywood Walk of Fame.
The Evening Standard quotes him as saying: "She's very cute and has a naughty side. I adore her. They shouldn't have denied her a star on the Walk of Fame."
Kim's sister Khloe is in the running to be the new host of The X Factor USA.
Cowell is also fond of Kim's boyfriend, musician Kanye West, and described him as an "innovator".
He said: "I think he's super-talented and an innovator. He knows what he's doing. Plus he's controversial and I like that."
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