Objective : This experimental study was carried out to investigate anti-coagulation effects and mechanism of Hongdeung-tang on the dissentimenated intravascular coagulation Methods : Each 10 rats were classified as normal gorup, control group and treated group. The control group was given a 0.5mg/ml endotoxin intra-vein injection and was occurred Disseminated Intravascular Coagulation(DIC). The treated group were orally administrated 1ml Hongdeung-tang concentration once a day for 6 days and then it was treated the same as the control group. We took the blood from heart and were investigated number of Platelet and white blood cell(WBC), fibrinogen concentration, prothrombin time(PT), activated partial thromboplastin time(APTT), interleukin-6(IL-6), Tumor Necrosis $Factor-{alpha}(TNF-{alpha})$, Prostaglandin $E2(PGE_2)$ from them. Results : There were a statistically significant increase of platelet and fibrinogen concentration in the treated group compared to the treated group. The PT was a significantly reduced in treated group compared to the control group. There was no significant change in numbers of WBC and APTT between control and treated group. On the contrary, the number of PT, IL-6, $TNF-{alpha}$, $PGE_2$ were significantly decreased in treated group compared to the control group. Conclusion : DIC which was occurred by endotoxin intravenous injection seems to related to the increase of IL-6, $TNF-{alpha}$, $PGE_2$ and Hongdeung-tang has an effect that supress those factors. we can assume Hongdeung-tang has an anti-coagulation effect by those supressing effect.