Abstract: The present study investigated the effect of Pulsatilla chinensis and its active ingredientsaponin on immunity and antioxidation of weaned piglets. One hundred and twenty crossbred pigs with the same age (282 d) were randomly divided into 6 groups with different diet including basal diet as control, basal diet with 150 mgkg-1 P. chinensis as treatment 2, basal diet with 300 mgkg-1 P. chinensis as treatment 3, basal diet with 12.5 mgkg-1 saponin of P. chinensis as treatment 4, basal diet with 25 mgkg-1 saponin of P. chinensis as treatment 5, basal diet with antibiotics as treatment 6. The results showed pigs fed diets supplemented with P. chinensis and saponin had significant greater amount (P0.05) of IFN, IL1, IgG and IgM in 14 d and C4 in 28 d, but had no significant effect（P0.05） on serum IgA and C3 content compared to pigs fed the control diet. Pigs fed diets supplemented with P. chinensis and saponin had significant greater (P0.05） serrum TAOC in 14 d and significant lower (P0.05） serum MDA in 14 d and 28 d compared to pigs fed the control diet. The experiment indicated that P. chinensis and its active ingredientsaponin improved immunity and antioxidation of pigs which were superior to antibiotics. Dietary supplement of 300 mgkg-1 P. chinensis or 12.5 mgkg-1 saponin was optimal.