This study was aimed to study the effects of Bacillus subtilis and bursin on growth performance,serum biochemical indices,and antioxidant indices of broilers.A total of one hundred and forty four 1-day-old Cobb-500 broilers were randomly allotted to four groups with three replications (twelve broilers in each replicate).The control group (group Ⅰ) was only fed basal diet.The bursin group (group Ⅱ) was fed basal diet and injected with bursin (0.01 mg/kg) at day 4 and day 7.Group Ⅲ was fed basal diet with Bacillus subtilis(1.0×106 cfu/g feed).Group Ⅳwas fed basal diet with B.subtilis (1.0×106 cfu/g feed) and injected with bursin (0.01 mg/kg) at day 4 and day 7.The trial lasted for 42 days.The results showed that the average daily gain in groupsⅡ,Ⅲ and Ⅳ were significantly higher than that in groupⅠ(P＜0.05) at day 21 and day 42,while the F/G value in group Ⅳ was the lowest and decreased 4.37% compared with group Ⅰ(P＞0.05).At day 21,contents of serum total protein in group Ⅲ and Ⅳrespectively increased 19.60% and 27.68%,comparing to group Ⅰ.At the same time,albumin contents in group Ⅲ and Ⅳrespectively increased 16.72% and 18.03%.The activities of CAT and GSH-Px in groupⅢ (on the 21th day) and Ⅳ (on the 42th day) were significantly higher than those in group Ⅰ(P＜0.05).Contents of serum MDA in groupⅡ,Ⅲ and Ⅳ were significantly lower than that in group Ⅰ(P＜0.05) at day 42.It was concluded that B.subtilis and when it combined with bursin could improve growth performance and increase contents of total protein and albumin in serum and the activities of CAT,GSH-Px.