In healthy volunteers, the plasma total tissue factor pathway inhibitor (TFPI) level was 68.7 ± 14.1 ng/ml; the plasma free TFPI level, 17.7 ± 5.4 ng/ml; the lipoprotein-associated TFPI (LP-TFPI), 51.1 ± 12.0 ng/ml; the free TFPI/total TFPI ratio 0.26 ± 0.07; and the plasma tissue factor levels were 149 ± 46 pg/ml.Plasma tissue factor levels in patients with disseminated intravascular coagulation (DIC) were significantly higher than those in pre-DIC patients or in non-DIC patients. Plasma total-TFPI, free-TFPI and LP-TFPI levels were significantly higher in DIC patients than those in pre-DIC patients or in non-DIC patients. Before the onset of DIC, the plasma levels of tissue factor gradually increased, and 3 days before the onset of DIC they were significantly higher than those in non-DIC patients. The plasma levels of tissue factor reached their highest level 1 day before the onset of DIC and gradually decreased after the onset of DIC. Plasma levels of total-TFPI, free-TFPI, and LP-TFPI gradually increased before the onset of DIC, and the total-TFPI and LP-TFPI reached their highest levels at the onset of DIC. Plasma free-TFPI reached highest level one day after the onset of DIC. During the clinical course of DIC, the plasma level of tissue factor was the first to increase, then that of LP-TFPI and finally the free-TFPI plasma levels. These differences in the peak plasma levels of tissue factor, free-TFPI, and LP-TFPI might be related to the clinical course of DIC.