The 34-year-old is said to growing increasingly jealous of half-sister Kylie, 17, who she believes is turning into a better looking version of herself.
A source told OK! USA: "Kim's been moaning to her mom for months now that Kylie's slowly morphing into a better looking version of her – and she's not happy about it."
The insider claimed Kim is so paranoid that she even confronted the teen.
"She fronted up Kylie and tore into her for copying her style and her look," the source said.
"Kylie denied it, of course, but she really does look more like Kim every day…
"Kim's got a huge ego and thinks Kylie's a threat to her brand… It's because Kylie's a much better looking version of her – and she knows it."
This comes after Kylie's rumoured rapper boyfriend Tyga, 25, seemed to confirm their relationship.
Posting a photo of Kylie to Instagram, Tyga wrote: "Certain things catch your eye, but only a few capture the heart."
Do you think Kylie is morphing into Kim?