Platelet GMP-140 and CD40L as specific markers of platelet activation play an important role in the morbidity and development of rheumatoid arthritis. The expression of GMP-140, CD40L increases in peripheral blood of AA rats. And they have correlation with voix pedis' swelling, AI. XFC could inhibit the inflammatory response through inhibiting platelet activation of AA rats, which means decreasing the expression of GMP-140, CD40L in peripheral blood. So, the voix pedis' swelling and AI were decreased as the result.