Objective:To study the effect of grape procyanidin (GPC) on the levels of plasma?-granule membrance protein 140 (GMP140) and thromboxane B2 (TXB2 ) in rats. Method:Wistar rats fed by high fat diet (HFD) were given GPC i.g. at different doses for 6 w, and the levels of plasma GMP140 and TXB2 were examined by radioimmunoassay (RIA). Result:Plasma GMP140 and TXB2 levels of high dose GPC were respectively 7.89?1.02ng/ml, 131.71?42.13 pg/ml, significantly lower than those of HFD group. Conclusion:GPC could inhibit the increase of plasma GMP140 and TXB2 induced by high fat diet in rats.