This study was a trial to evaluate the level of zinc and its effect on T tymphocyte function In chronic renal failure patients associated with active schistosomaJ Infection This study Included 50 cases 20 patients with chronic renal failure under regular hemodialysis and associated with active. schistosomal infection. 20 patients with chronic renal failure under regular hemodialysis and not associated with schistosomal infection and 10 subjects as a control group. For each case of this study; full history, complete clinical examination , rectal snip , blood urea. serum creatinine , serum zinc and T - lymphocyte function were all done before and after 4 weeks Zinc supplementation ( 660 mg / day) . The level of serum zinc was significantly decreased in both groups as compared with the control group. The level of serum zinc in patients was not significantly higher after than before zinc supplenentation . There was non - significant increase of E - rosette percentage after zinc supplementation for both groups . There was non - significant increase of Blastoid transformation percentage after zinc supplementation for both groups. We may conclude that zinc supplemenation for periods more than 4 weeks is of benefit for the level of serum zinc and T - lymphocyte function in patients with chronic renal failure with schistosoma! infection