This study has been undertaken to find out whether urinary zinc excretion, which is already increased in patients with thalassemia, is further increased by usual and high doses of desferrioxamine (DF). A total of 11 beta-thalassemia major patients were included. DF infusions have been performed with doses, either 50 mg/kg or 150 mg/kg. Nine age and sex matched normal children were taken as the control group. The mean basal-Zn excretion of the patients was significantly higher than the mean Zn excretion observed in controls. No significant difference is observed between the mean Zn excretion obtained on different doses of DF. However, they are both significantly higher than the mean basal-Zn levels of the controls.