The present study was designed to determine the effect of using different levels of selenium (Se) on the productive performance of White Hi-line laying hens. A total of 60 White Hi-line hens aged 16 weeks housed individually in cages (4 hens/cage) and divided into 3 equal groups was used. They were fed on the basal diet supplemented with 0 (as control group),5 and 10 ppm Se (as sodium selenate).The body weight, egg mass, feed consumption, feed conversion, egg quality measurements and some blood parameters were taken.Selenium concentration in some organs was determined. Main results obtained can be summarized as follows: -Supplementing the basal diet with 5 and 10 ppm Se caused significant decrease in body weight, egg number, egg mass and feed consumption. -Shell weight, shell thickness and egg breaking strength were significantly decreased by supplementing the basal diet with 5 and 10 ppm Sc. -Hens fed on diets supplemented with lOppm Se gave higher mortality rate than those of 0 and 5 ppm Se fed groups. -The results obtained showed that the dietary Se supplementation caused significant increase in Se concentration of plasma,liver,kidney and muscles as compared to the control group. -White Hi-line layer diet should not contain more than 5 ppm Sc.