Klay Thompson is a perennial All-Star, 3-Point Contest winner, and 2-time NBA champion with the Golden State Warriors ... but he's NOT Dunk Contest material.

Warriors haters will love this. Klay's in China to promote his Chinese brand Anta shoes, but he might want to lace 'em up again before he tries another dunk ... because he failed miserably in front of fans with this attempt.

Gotta admire the effort, though -- 360 dunks aren't easy. And on the bright side ... maybe Klay can score a deal with Sprite now too.