The acute oral toxicity of organogermanium, Ge-132 was evaluated in rats andmice. The changes of body weight and clinical signs were observed for 14 days after the oral administration of Ge-132, from 0.31 g/kg up to 5 g/kg for SD rats and from 1.25 g/kg up to 5 g/kg for ICR mice. No death and toxic effects were observed for 14 days. The body weight of rats was significantly decreased 1 day after the administration in the maximum dosing group, but the decrease of body weight returned to control level 3 days after dosing. No significant changes in 132. Therefore, Ge-132 has no special toxic effects up to 5 g/kg, and LD* values of Ge-132 Ge-132 are above 5 g/kg in rats and mice.