METHODS: 80 C57BL/6J mice were randomly divided into 2 groups, blank control group (A) (n=20) and model group (B) (n=60). Mice were exposed to room air or cigarette smoke for 24 weeks. At the end of 24th week, 10 mice from each group were randomly selected to determine parameters, including the mouse pulmonary function (PF), the hematoxylin and eosin (H&E) staining sections, the alcian blue-periodic acid Schiff (AB-PAS) staining sections, the protein level and the mRNA expression level of Toll-like receptor 4 (TLR4), nuclear factor-κB (NF-κB), phospho-NF-κB (p-NF-κB), mucin 5B (MUC5B) and mucin 5AC (MUC5AC) of lung tissues. Then the rest mice in group B were randomly and evenly divided into 5 sub-groups: blank control treatment (C), positive control treatment (D), low dose treatment (E), medium dose treatment (F) and high dose treatment (G). Afterwards by oral injection, the mice in group A and C were given by physiological saline, while the mice in group D, E, F and G were given by carbocisteine or different dose Bufei granules. The treatment lasted for 12 weeks. Finally we measured the same indexes as before.