Objectives: To evaluate the feasibility of platelet activation parameters served as diagnostic and prognostic marker in the course of coronary disease. Methods: platelet activation parameters, Tn1(cardiac troponin I), CK-MB (creatine kinase-heart type), fibrinogen and DD (D-dimers) were measured with an enzyme immunoassay (Bio-Check) and diagnostic sensitivity was compared among them. Result: platelet activation parameters, concentration increase systematical y with the advancement of coronary artery disease. As diagnostic and prognostic marker for coronary artery disease, the sensitivity is higher than that of TnI, CK-MB and DD. Conclutions: Platelet activation parameters may serve as at ractive diagnostic and prognostic markers in the assessment of the risk for unstable atheroma in the course of coronary artery disease.