The current experiment was carried out to test the ability of supplementing quail diet with natural antioxidants to improve antioxidant status of growing Japanese quail and alleviate aflatoxin B1 adverse effects during the summer season. Three levels each of curcumin and silymarin (zero, 250mg and 500mg/kg diet) were combined to compose 9 experimental diets and the diet that contains zero levels from each natural antioxidant acted as a control basal diet. Three hundred and sixty one-day-old Japanese quail chicks were distributed randomly into nine experimental groups where each group contained 4 replicates with 10 chicks per each. Each experimental group fed only one diet for five weeks where growth performance parameters were recorded. The following results were obtained. Significant improvement was detected in final body weight and entire body weight gain for quail fed the diet supplemented with 250 mg /kg diet from both curcumin and silymarin compared with quail fed the control diet. Final body weight and entire body weight gain gained more improvement with increasing curcumin and silymarin up to 500mg/kg diet. Curcumin and silymarin supplementation didn't affect significantly the feed intake, feed conversion carcass parameters and plasma proteins fraction. Blood antioxidant parameters were improved by curcumin and silymarin supplementation. The level of aflatoxin B1 in liver and muscles were significantly decreased by curcumin and silymarin supplementation. From the current experimental results, we can recommend supplementing diets with curcumin and silymarin to improve growth performance .