Thirty-six healthy Guangfeng goat lambs aged around 45 d with body weight(6.30±0.54) kg were selected and randomly divided into 3 groups with 12 lambs in each group. The control group was fed a basal diet(CON), and the experimental group was fed a basal diet supplemented with 100 mg/kg(Q100) or 200 mg/kg(Q200) of quercetin for 15 d. After weaning at 60 day of age, the lambs were further fed for 15 d. Body size indices of lambs were measured 15 d before weaning, on the day of weaning and 15 d after weaning. In addition, serum biochemical, immunological and antioxidant parameters were measured in lambs on the day of weaning and 15 d after weaning. The results showed that 1) the addition of quercetin to the basal diet had no significant effect on body height, chest circumference, body length, body weight, average daily gain, average daily feed intake and feed-to-weight ratio of weaned Guangfeng goat lambs. 2) On the day of weaning, serum glutamate aminotransferase(GOT) activity of lambs in the Q200 group was significantly increased by 1.89 folds compared with CON group(P<0.05); at 15 d after weaning, the serum alanine aminotransferase(ALT) of lambs in the Q200 group was significantly increased by 1.02 folds compared with CON group(P<0.05). 3) On the day of weaning, the serum IgA concentration of lambs in the Q100 group was significantly increased by 1.48 folds compared with CON group(P< 0.05), while the IgM and IL-1β concentrations were decreased by 26.97% and 50.81%, respectively; at 15 d after weaning, the serum IgG concentration of lambs in the Q200 group was significantly increased by 1.28 folds compared with CON group, whereas the IL-1β concentration was decreased by 46.71%(P<0.05). 4) On the day of weaning, the serum CAT activities of lambs in Q100 and Q200 groups were 1.61 and 1.82 folds higher than those in the CON group, respectively, while they were 2.98 and 2.84 folds higher than those in the CON group on 15 d after weaning(P<0.05); at 15 d after weaning, the serum T-SOD and GSH-Px contents of lambs in the Q100 group were 1.59 and 1.24 folds higher than those in the CON group, respectively(P<0.05), and the serum T-SOD and GSH-Px contents of lambs in the Q200 group were 1.65 and 1.32 folds higher than those in the CON group, respectively(P<0.05). In conclusion, quercetin can improve the antioxidant property and immunity of early weaned Guangfeng goat lambs, and inhibit the inflammatory response to alleviate the early weaning stress of Guangfeng goat lambs.