Los Angeles socialite Kim Kardashian and her sports star boyfriend Reggie Bush are selling their cars for charity.

Kardashian's white Ranger Rover and Bush's Mercedes Shark II custom car have been put up for bidding on website auction house eBay.com as part of a Kardashian family "closet cleaning".

Kardashian says, "A percentage of the proceeds from this and all my auctions will go to my favourite charity, the Dream Foundation, a really wonderful organisation that grants wishes to terminally-ill adults. I volunteer for them and love the way they're making a difference in the world... one person at a time."

The auction is a venture of the eBay Giving Works project.