Abstract: Objective To evaluate the value of a new platelet function test PFA P2Y (PFA-200) in monitoring clopidogrel treatment for cardiovascular disease in elderly patients. Methods Fifty-six elderly patients receiving clopidogrel therapy in the Department of Cardiology of General Hospital of PLA from March to August in 2016 and 85 healthy volunteers were recruited for analysis. All the subjects underwent PFA P2Y, LTA (light transmittance aggregometry) and TEG (Thromboelastograph) tests, and Spearman correlation coefficients were used to test the associations between test results. The agreement among the 3 platelet function test methods was assessed using Cohen’s kappa coefficient. Results Correlation coefficient (r) was -0.701 (P< 0.001) between PFA P2Y and LTA, and 0.475 (P<0.001) between PFA P2Y and TEG. The agreement was 75% between PFA P2Y and LTA and 67.9% between PFA P2Y and TEG. The κ value was 0.434 (P=0.001) between PFA P2Y and LTA and 0.242 (P=0.046) between PFA P2Y and TEG. With ADP-induced maximum platelet aggregation rate of LTA >50% as the laboratory clopidogrel resistance, the cut-off value of PFA P2Y was 119 s (AUC=0.733) with a sensitivity of 75.6% and a specificity of 73.3% . Conclusion PFA P2Y has a moderate correlation and agreement with LTA, but has a poor correlation and agreement with TEG. PFA P2Y can be useful for assessing the effects of clopidogrel therapy and the association of the cut-off value (119 s) with the long-term clinical ischemic events needs be confirmed in further study.