Abstract: Amidantel, a new broad spectrum anthelmintic, was studied for its teratogenicity in mice. The mice were given orally the drug in a dose of 60, 30, 15mg/kg/d X 10 ((?)1/10, 1/20, 1/40 LD50) during d6 to d15 period after gestation. A known teratogen, dexon, at the dosage of 20mg/kg/d X 10 was usod as positive control. Pregnant mice were sacrificed on d18 and fetuses were subjected to tetratological investigation. The results showed that amidamel did not manifest significant embryotoxicity in our experiments.