Objectives : The purpose of this study was to investigate acute toxicity of orally-treated Sagunja-tang(Sijunzi-tang) in ICR mice. Methods : In this study, we investigated the acute toxicity of water-extracted Sagunja-tang(Sijunzi-tang). Twenty-five mice completed 14 days of oral Sagunja-tang(Sijunzi-tang) at respective doses of 0 (control group), 2560, 3200, 4000 and 5000 mg/kg. Results : We observed survival rates, clinical signs of male ICR mice with acute toxicity, change of body weight and autopsy. Conclusions : Compared with the control group, we could not find any toxic alteration in anytreated groups (2560, 3200, 4000 and 5000mg/kg). LD50 of Sagunja-tang(Sijunzi-tang) was over 5000 mg/kg and it is very safe for ICR mice.