An experiment was conducted to investigate the effect of different graded levels of chromium picolonate on performance of broiler chicks, some digestive enzymes activity, carcass yield and some blood constituents. For this purpose three hundred day old Cubb broiler chicks were allocated into five treatment groups. For five weeks experimental period, four groups of birds were fed on corn soy-basal diets supplemented with 0.25mg, 0.5mg, 0.75mg or 1mg/kg diet chromium of chromium picolonate whereas the fifth group was the control. Average body weight improved due to feeding supplemental chromium diets. The group of birds fed 0.5mg chromium picolonate recorded the highest body weight (1888g) followed by those fed 0.75mg Cr (1872g) compared with (1788g) for control. Feed consumption values were not affected by treatments for the entire experimental period. Feed conversation (g feed/g gain) improved as a result of feeding dietary chromium. The beneficial effects of chromium supplementation may be related to its effect on stimulating digestive enzymes activity and immune response. Amylase enzyme activity was significantly elevated in jejunum and ileum due to feeding chromium enriched-diets, while lipase enzyme was slightly increased due to treatment in jejunum only. Trypsine and chemotrypsine enzymes were not affected by treatments. Dressed carcass and breast meat yield percentages were increased due to adding chromium into diets while; thigh, drumstick or back percentages were not affected.                 Supplemental organic chromium significantly increased plasma concentration of glucose, total lipids, cholesterol and triglycerides while plasma high density lipoprotein cholesterol (H.D.L.) was not affected. Plasma total protein and globulin increased significantly due to treatments while, plasma albumin was not affected. Albumin to globulin ratio decreased by inclusion of chromium into broiler diets that may indicate enhancement in immune response of birds.