BACKGROUND: D-dimer is a specific marker of secondary fibrinolysis. D-dimer assay is widely used in the diagnosis of disseminated intravascular coagulation, deep vein thrombosis, pulmonary embolism, and arterial thromboembolism. Enzyme linked immunosorbent assays have been validated as the reference method for plasma D-dimer measurement, but it took long time. We evaluated the analytical performance of new automated coagulation system, ACL TOP, for quantification of D-dimer. METHODS: The total plasma D-dimer concentrations were measured by Nycocard and ACL TOP. To test the linearity, a serial dilution samples were prepared and measured. Between run precision of the ACL TOP D-dimer assay was evaluated with HemosIL D-Dimer controls for 20days. The correlation was evaluated using 75 plasma samples from patients. ACL TOP was evaluated according to CLSI guidelines. RESULTS: ACL TOP showed good linearity (r=0.9996) and between run coefficient of variation was within 4.0%. Coefficient of correlation between Nycocard and ACL TOP was 0.798. Positive concordance rate of ACL TOP was 67%, and negative concordance rate of ACL TOP was 80%. CONCLUSIONS: Since the ACL TOP showed a satisfactory precision, linearity, and comparative high correlation with Nycocard, and is more convenient and automatic than the Nycocard, it should be potentially beneficial in the clinical laboratories.