Objective:To establish the rat model of chronic obstructive pulmonary disease(COPD),investigate the mechanism of airway remodeling induced by imbalance of protease and protease inhibitors in COPD and study the effects and possible mechanism of Qinma Formula in the treatment of COPD. Methods 70 SPF rats were randomly divided into the normal group,model group,Qinma Formula groups with low-,middle- and high-dose,Liujunzi Decoction group and aminophylline group,10 rats in each group. Rat model of COPD was established by intratracheal injection of pyrosulfuryl chloride solution and mixture of lipopolysaccharide and pepsin combined with smoking. The respiratory function of rats was measured by noninvasive respiratory function apparatus. The morphology of lung tissue and bronchus were observed under light microscope. The serum content of transforming growth factor-β,1, (TGF-β,1,) was detected by ELISA. The expressions of matrix metalloproteinases-9(MMP-9)and tissue inhibitor of metalloproteinnase-1(TIMP-1)in lung tissue were determined by immunohistochemistry.  Results: Compared with the model group,Qima Formula could significantly decrease the respiratory frequency(P,<,0.05),and increase the respiratory flow(P,<,0.05). The thickness of airway wall and smooth muscle were significantly decreased in the Qinma Formula groups with middle-and high-dose(P,<,0.05).The serum content of TGF-β,1, was significantly decreased in the Qinma Formula groups with low-,middle- and high-dose(P,<,0.05).The expressions of MMP-9 and TIMP-1 were significantly decreased in the Qinma Formula groups with middle- and high-dose(P,<,0.05).  Conclusion: Qinma Formula could significantly improve the respiratory function of rats and down-regulate the expressions of MMP-9 and TGF-β,1, in lung tissue,and thus reduce the destruction on alveolar and tracheal structures and reverse the airway remodeling.