JaVale McGee to Kanye -- MAKE BIGGER SHOES ... I Need a Size 18!!

NBA star JaVale McGee says size definitely matters when trying to cop some Yeezys ... telling TMZ Sports he can't style in the hottest shoe of 2015 ... because Kanye doesn't make a SIZE 18!!

The 7-footer was enjoying the beginning of the All-Star break at 1Oak in L.A. when we asked the notorious sneakerhead when we'd see him in the most talked about shoe in the world right now.

The answer? NEVER ... or at least until Mr. West and Adidas makes them in sizes that accommodate JaVale's gargantuan hooves ... which McGee says would cost A TON of cash for the material alone!