Objective：To investigate the inhibitory effects of puerarin on airway inflammation and Th2 immunity in a murine model of chronic asthma. Methods：Thirty-two female BALB/c mice were randomly divided into four groups，including the control group，the ovabumin(OVA)group，the puerarin group，and the budesonide group，8 mice in each group. In the latter three groups，chronic asthmatic models were established by OVA allergy and activation for 12 weeks. Twenty -four hours after the last airway provocation， acetylcholine(Ach)was administered via caudalis vein to measure airway resistance by pulmonary function detector. The airway inflammation and hypersecretion in the lung were assessed by hematoxylin & eosin(HE)and periodic acid Schiff(PAS)staining， respectively. The levels of interleukin(IL)-4 and IL-13 in bronchoalveolar lavage fluid(BALF)and total immunoglobulin E(IgE)in serum were measured by ELISA. The protein expression of thymic stromal lymphopoietin(TSLP)was determined by Western blot. Results：As compared with the control group，the airway hyperreactivity，airway inflammation，cell count and eosinophil percentage in BALF，levels of total serum IgE and BALF IL-4 and IL-13，and TSLP expression in the lung were significantly increased in the asthma group(P ＜ 0.05). As compared with the asthma group，all the above indices mentioned in the puerarin group and the budesonide group were decreased significantly(P ＜ 0.05). Conclusion：Puerarin alleviates the airway inflammation，hyperresponsiveness，and Th2 immunity by down-regulating the expression levels of TSLP in a chronic experimental asthma.