The results of current study showed that Se supplementation, at the levels of Se used in this study, increased significantly Se levels in plasma, liver and muscles, as well as activity of plasma glutathione peroxidase in ducks. The highest live weight was achieved by addition of 0.4 mg/kg of Se in diet. Moreover, chemical analysis of meat revealed differences in moisture,protein and lipid content among groups of ducks which had been fed different Se-diets.