Aim To determine the platelet surface expression of CD62P and CD40L in type 2 diabetes mellitus patients(T2DM)with coronary heart disease(CHD)and to explore the relationship between them and serum high-sensitivity C reactive protein(hs-CRP)level.Methods The platelet surface expression of CD62P and CD40L were measured by flow cytometry at fasting state in 97 consecutive patients,including 34 CHD patients,33 T2DM patients,and 30 T2DM with CHD patients.30 subjects were served as a control group.The correlation between platelet CD62P and CD40L and serum level of hs-CRP were investigated.Results Platelet CD62P and CD40L levels and serum level of hs-CRP in the T2DM with CHD patients were significantly higher than those in the control group,CHD patients and T2DM patients(P<0.01).The levels of platelet CD62P and CD40L were positively correlated with serum level of hs-CRP(r=0.343 and 0.495,both P<0.05).Conclusions Platelet surface expression CD62P and CD40L levels,which are significantly higher in the T2DM with CHD patients and were positively correlated with serum level of hs-CRP,may be useful markers for predicting the presence of coronary artery disease in T2DM patients.