Abstract: The reduction rate of the warm burdens was found to be 57.6～71.3%, 99.2～100.0% and 45.9～69.0% when it was given orally to mice (3000mg/kg/day×28),rabbits (200～600 mg/kg/day×14～28) and dogs (140.6～281.0 mg/kg/day× 28) respectively.Combined medication of Pararosaniline with sodium antimony subgallate, Niridazole or furopromide resulted in decrease of the dosage of both drugs; incease of the therapeutic effect against experimental schistosomiasis and shortening of the therapeutic course.The acute oral LD₅₀ of Pararosaniline pamoate was found to be more than 12 g/kg in mice, and the subacute (28 dag) oral LD₆₀ was found to be 458.4±28.4 mg/kg/day in rabbits.Other pharmacological and toxicological activities and the metabolic fate of pararosaniline pamoate was also reported.