The effect of zinc on manganese induced testicular injury was investigated. It was observed that daily intraperitoneal administration of MnSO₄•4H₂O (6 mg Mn/kg) to the rats for 30 days produced degeneration of some of the seminiferous tubules whereas simultaneous administration of ZnSO₄•H₂O (2 mg/kg) to these rats pro-tected them from the toxic effects of manganese on testis. The concentration of manganese in testis of rats treated with manganese and zinc salts was lower as compared to that observed in testis of rats treated with manganese alone, while zinc content in this group was significantly higher than in the testis of animals treated with zinc alone. The exact mechanism of interaction of these two metals in pro-tecting testis from injurious effects of manganese is not known.