Khloe Kardashian's booty is so big -- it looks like she has a basketball in her skirt. The 30-year-old's got one serious Badonkadonk -- or more like Badonka-dunk!

Watch out Kimbo -- Khloe's butt is giving you a run for your money. We bet Kimmy hopes that Khloe does't decide to oil up that derriere of hers and give her a run for her money for the biggest and best Kardashian bottom.

The reality star donned a skintight leather skirt, leather and pumps to film Keeping Up With The Kardashians reality show at Fusion motors in Los Angeles on Monday.

But seriously -- that ass -- it's like the Eighth Wonder of the World!