Hairtech International has accused the socialite of wearing hair from a competitor, despite having signed a contract to promote its own products.
The lawsuit claims that Hilton was paid $3.5 million to promote their products, and the company are now asking for $35 million in damages.
They're also claiming that the heiress missed a launch party in 2007 because she was serving a prison sentence for a driving offence, which apparently didn't bode well with the 'lifestyle' of their campaign!
However, Paris is fighting back and a spokesperson for Hilton has said:
"There is no merit whatsoever to any of these claims. "We will pursue all of our defenses vigorously and any potential counter claims."
