Kardashian, 28, and Lopez, 38, will be co-hosts on the reality competition this season with the official announcement expected later this week, reported Us magazine.
"They are finalizing their deals to take the hosting duty They two want to do it, and the show is keen to have them," a source said.
The US version of 'The X Factor' has been looking for new hosts after Steve Jones was fired at the end of the inaugural season.
'X Factor' started second season on US television last month with audition episodes in which Britney Spears and Demi Lovato joined LA Reid and Simon Cowell on the judge's panel.