This experiment was conducted to study the effects of different levels of α-galactosidase on growth performance and nutrient availability in yellow broilers. Five hundred 8-day-old yellow broilers were randomly assigned to five groups with four replicates and twenty-five chicks in each replicate. Experiment was divided into 2 periods (8～28 d and 29～56 d) and lasted 49 days. Group Ⅰ fed positive control diets (PC, ME: 8～28 d 11.92 MJ/kg, 29～56 d 12.34 MJ/kg); group Ⅱ fed negative control diets (NC, ME: 8～28 d 11.71 MJ/kg, 29～56 d 12.13 MJ/kg). Group Ⅲ～Ⅴ were fed NC diets supplemented with 100, 150 and 200 mL/t of α-galactosidase, respectively. The results showed that the average daily weight gain (ADG), average daily feed intake (ADFI), 8～28 d and 8～56 d feed to gain ratio (F/G) and survival rate had no significantly difference among five groups (P>0.05), but 29～56 d F/G in group Ⅲ～Ⅴ was lower than that in PC group (P>0.05) and NC group (P<0.05),and 8～56 d F/G in group Ⅲ～Ⅴ was also lower than that in NC group and PC group (P>0.05). The apparent metabolizability of DM, CP, energy and the apparent metabolizable energy in group Ⅲ～Ⅴ had no significant difference (P>0.05) compared with those of NC and PC group. The apparent digestibility of Val, Leu and Lys in group Ⅲ～Ⅴ were significantly higher than that in NC group (P<0.05), but the apparent digestibility of total AA had no significant difference among 5 groups (P>0.05). It was concluded that the supplementation of α-galactosidase in NC diets could reduce F/G of 29～56 d yellow broilers and improve the apparent availability of some AA.［Chinese Journal of Animal Nutrition, 2009，21(6):924-930］