The acute toxicity of orally administered Yan-Sheng health liquid (YSHL), water extracts from twelve Chinese drugs (Cervi Cornu, Lonicerae Flos, Foeniculi Fructus, Glycyrrhizae Radix, Liriopis Tuber, Raphani Semen, Bombyx, Ginseng Radix alba, Cinnamomi loureirii Cortex, Epimedii Herba, Zingiberis Rhizoma, Lycii Fructus) was evaluated in male and female Sprague-Dawley rats and ICR mice. Rats and mice aging 5 weeks were gavaged with 0, 2.0, 3.0, 4.4, 6.7, 10.0, 66.7, or 100.0 ml/kg of YSHL. No animal died by oral treatment and no toxic symptom was observed in the treated animals during 5 days. The body weight of the treated animals was not significantly different from the controls. The results of macroscopic examination on the organs of the treated animals revealed no abnormal findings. Therefore, it was concluded that YSHL was practically non-toxic when it was orally administered to rats and mice, and its LD50 was suspected to be greater than 100 ml/kg in rats and mice.