Thrombin-activatable fibrinolysis inhibitor (TAFI) is a carboxypeptidase that downregulates fibrinolysis and might play some roles in the pathogenesis of disseminated intravascular coagulation (DIC). We prospectively examined the plasma TAFI antigen levels in patients highly suspected to be suffering from DIC. Patients were subdivided into overt DIC and non-DIC groups according to a DIC scoring system. The Sepsis-related Organ Failure Assessment (SOFA) scores were concurrently calculated on patients with sepsis. Overall, there were 23 non-DIC patients and 20 patients with overt DIC. Their baseline characteristics were similar, but patients with overt DIC had much more aberrant coagulation tests and higher lactate dehydrogenase levels. However, there was no significant difference between overt DIC and non-DIC patients regarding their TAFI antigen levels [median/interquartile range (IQR) 74.41/13.98 and 75.29/15.16, respectively, p=0.543]. On regression analysis, TAFI antigen levels were not correlated with either C-reactive protein levels or various coagulation test results. In patients with sepsis (n=31), TAFI levels among three risk groups stratified by low (<or=5), intermediate (6-10), and high (>or=11) SOFA scores were not statistically disparate (median/IQR 65.24/15.14, 74.63/13.79, and 75.29/21.51, respectively, p=0.684), either. Our result indicated that plasma TAFI antigen levels did not vary significantly between patients with or without DIC. Further, they did not possess any correlation with the severity of organ injury in patients with sepsis. The role of TAFI antigen in the pathogenesis of DIC needs further elucidation by future studies.