Abstract: In order to assess whether the effect on platelet function will persist with prolonged Gliclazide treatment,10 patients with NIDD who were not controlled by diet alone and treated with Gliclazide were prospectively studied based on a previous report and followed up for 6 months.The results showed a significant and persistent inhibition in the mean platelet adhesiveness,in platelet aggregation induced by ADP and in viscosity of plasma （P＜0.01 or∠0.05）.Yet there no apparent influence on hemostatic mechanism.In contrast to the rapid decrease of hyperglycemia,the depression in platelet function was rather slow but progressive.The authors believe that the antiplatelet effect of drug connot be simply considered as secondary to the control diabetes.One appears,such an effect will persist for at Ieast up to 6 months while treatment is going on.