To investigate the Qiaoqin Qingfei Formula in improving airway inflammation and its possible mechanism. Methods:Fifty female SD rats with asthma were randomly divided into 5 groups：normal group, model group, dexamethasone group and, low and high dose group of Qiaoqin Qingfei Formula. The contents of interleukin-1 (IL-1), interleukin-5 (IL-5) and interferon gamma (IFN-γ) in bronchoalveolar lavage fluid (BALF) were detected with ELISA method after administration. The proteins expression of the Erk1/2 of the lung tissues and the TGF-β1 of the bronchial tissues were analyzed by Western blot method and the mRNA expression of ERK1/2 of the bronchial tissues were analyzed by Real-time PCR. Results:Compared with normal group, the mRNA expression of ERK and the protein expression of TGF-β1 were significantly increased (P<0.01). Compared with the model group, all the treatment groups significantly decreased the expression of the ERK mRNA and the protein of TGF-β1 (P<0.05-0.01). Conclusion:Qiaoqin Qingfei Formula can significantly improve the symptoms of respiratory tract which has a protective effect on asthmatic rats. Its mechanism may be related to the inhibition of the phosphorylation of ERK signaling pathway, regulation of IL-4/IFN-γimbalance and reduction of inflammatory cell infiltration.