Purpose: This study was performed to evaluate the single dose oral toxicity of Gwibi-tang extract in ICR mice. Methods: 0(control group), 1250, 2500 and 5000 mg/kg of Gwibi-tang extracts were orally administered to 20 male and 20 female ICR mice. After single oral administration of Gwibi-tang extract to ICR mice, we observed number of the death, clinical signs, changes of body weights for 14 days. After 14 day of Gwibitang extract administration, all mice were sacrificed and major organs were observed. Results: Compared with the control group, we could not find any toxic signs in the mortalities, clinical signs, body weight changes, necropsy findings and hematological values in all treated groups(1250, 2500 and 5000 mg/kg). Conclusions: $LD_{50}$ value of Gwibi-tang extracts may be over 5000 mg/kg and it may have no side toxic effect to ICR mice.