This experiment was conducted to study the effects of Astragalus polysaccharides (APS) on growth performance, viscera indices and antioxidant capacity of broilers aged 1 to 14 days. Seventy-two healthy 1-day-old Avian broilers were randomly assigned to 4 dietary treatments with 3 replicates per treatment and 6 broilers per replicate. The broilers were fed the basal diet supplemented with 0, 0.2%, 0.4% and 0.6% APS, respectively. The feeding trial lasted for 14 days. The results were showed as follows: 1) there were no significant effects of APS on growth performance (P>0.05); 2) APS increased liver index, pancreatic index, and immune organ indices significantly in 7-day-old broilers (P<0.05), but no significant effects on 14-day-old broilers were found (P>0.05); 3) adding APS to the diets could increase serum and liver antioxidant enzyme activities and decrease malondialdehyde (MDA) content in both 7- and 14-day-old broilers. These results indicate that APS can improve organ development in broilers aged 1 to 7 days, and increase the activities of antioxidant enzymes in serum and liver to strengthen the immunity and antioxidant capacity of broilers, but there are no significant effects on the growth performance of broilers aged 1 to 14 days.［Chinese Journal of Animal Nutrition，2011，23（3）：486-491］