Objecfive To evaluate the effects of cilostazol on the prevention of microvascular complications in diabetic patients.Methods 60 diabetic patients with microvascular complications were orally given cilostazol for 1 month.Changes of Mean platelet volume (MPV),plateletcrit (PCT),platelet distribution width (PDW) and platelet count (PLT) were studied.Results With administration of cilostazol,MPV and PDW decreased significantly. Conclusion Cilostazol improves platelet parameters,suggesting that it could prevent the progression of microvascular diseases.