Abstract: OBJECTIVE To investigate the effect of Qiaoqinqingfei Ji on immune regulation Th1/Th2 imbalance and its mechanism in the rat asthmatic models. METHODS Asthmatic model radts were established by introperitoneal injection of 10% OVA on the first day and the eighth day. Fifteen days after, gave atomization inhale 1% OVA, once a day for two weeks. At the same time, normal saline, dexamethasone, aminophylline and Qiaoqinqingfei Ji were used for intervention treatment respectively to asthma model rats, once a day, last for four weeks. The effect of medicine on the asthma degree, asthma latency period and the pathological changes of bronchial and lung tissue, the contents of IFN-γ, IL-4, IL-5 and the IFN-γ/IL-4 ratio in bronchus alveolus lavage fluid of asthma model were observed. And compared with dexamethason group and aminophylline group. RESULTS Qiaoqingqifei Ji obviously improved the asthma degree, extended asthma latency period, decreased the content of IL-4, IL-5 (P<0.05 or P<0.01), increased the content of IFN-γ and the ratio of IFN-γ/IL-4. Pathological results revealed that the bronchial mucosa epithelial cells and goblet cells hyperplasia, alveolar contains secretions and inflammatory cells infiltration, luminal stenosis in the model group. And these changes were released obviously in the medicine group. CONCLUSION Qiaoqingqifei Ji can effectively adjust Th1/Th2 imbalance in asthmatic rats, improve asthma status and reduce asthma attacks.