Objectives: Samul-tang(Siwu-tang) has been traditionally prescribed a medicine as a restorative. Methods: In this study, we investigated the acute toxicity about water-extracted Samul-tang(Siwu-tang). Twenty-five mice completed 14 days of oral Samul-tang(Siwu-tang) at the respective doses of 0(control group), 2560, 3200, 4000 and 5000mg/kg. Results: We observed survival rates, general toxicity, change of body weight, and autopsy. Conclusions: Compared with the control group, we could not find any toxic alteration in all treated groups (2560, 3200, 4000 and 5000mg/kg). $LD_{50}$ of Samul-tang(Siwu-tang) was over 5000mg/kg and it is very safe to ICR mice.