Abstract: S75029 (indane oxime) is a new type of antischistosomal drug. When administered orally to mice, rabbits or dogs infected with Schistosoma Japonicum, some vermicidal effect was observed. But even at maximum tolerated dosage in a 3～20 day course, the worm reduction rate was only about 40%. After its administration to mice at the dosage of 1/2～2/3 LD₅₀ for 7 or 10 days, different degree of pathological changes were observed in stomach, intestine and kidney. All these tissue lesions disappeared one month after the cessation of treatment.