The pic was "A sneak peek at our Quick Trim Photo shoot!" she posted on her Twitter page.
The curvaceous blonde stunner who is now a spokesperson for the weight loss program Quick Trim posted the photo showing her blowing a kiss while wearing a tiny black bikini on Wednesday.
She took the sexy shot with her BlackBerry when she found some downtime during the shoot.
Kim and sister Khloe are both spokesmodels for the weight-loss product. The "Keeping Up With the Kardashians" star said the product has helped boost her metabolism.
"It's definitely a lifestyle change, but when there are products available like Quick Trim, it's so much easier to lose the extra pounds you've been dying to get rid of!" she wrote on her website in July.