The acute toxicity of STB-HO-BM was evaluated in Sprague Dawley (SS) rats and beagle dogs. STB-HO-BM was administered orally to rats at dose levels of 0 and 2,000mg/kg/day and to dogs at dose levels of 0, 500, 1,000 and 2,000 mg/kg/day. In these experiments, there were no death and clinical changes which were related to STB-HO-BM administration. In addition, there were no significant changes between control and treated groups in body weights and autopsy findings. In conclusion, the administration of STB-HO-BM 2,000 mg/kg in SD rats and up to 2,000mg/kg in beagle dogs was proved to be safe, and it is thought that STB-HO-BM may not show any toxicity in its clinical use.