Abstract: The effects of combined treatment of Sb-71 with some metal salts such as cupric sulfate, magnesium sulfate, zinc sulfate, cupric chloride, magnesium chloride and zinc chloride were investigated in mice bearing Ehrlich ascites carcinoma. It was found that simultaenous administrations of Sb-71 (15 mg/kg) and cupric sulfate (1.5-3 mg/kg) produced a marked potentiation of inhibition of the growth of the carcinoma, and prolonged significantly the survival time of the mice. The density and the total number of ascites carcinoma cells were considerably decreased than those in the group treated with Sb-71 alone. Cupric sulfate alone at dosages of 1.5-3 mg/kg/day had no therapeutic effect on Ehrlich ascites carcinoma. Magnesium sulfate, zinc sulfate, cupric chloride and magnesium chloride did not influence the carcinostatic activity of Sb-71, whereas zinc chloride showed some antagonistic action against the therapeutic effect of Sb-71.