Objective To establish a cigarette smoke-induced chronic obstructive pulmonary disease (COPD) mouse model.Methods C57 mice were randomly divided into COPD model group and normal control group.The model group mice were exposed to cigarette smoke for twice per day,2 hours for each time with nine cigarettes per hour,6 days every week in 6 months.Control mice were exposed to room air only.During the six-month-exposure,both groups of mice were weighed every week and their pulmonary functions were measured once every month.Then the mice were dissected after the last pulmonary functions determination and the succeed of the model establishment was judged by evaluating the following parameters:the inflammatory cell numbers and mucin MUC5AC levels in bronchoalveolar lavage fluid (BALF),the phenotypes on lung pathological changes,and the parameters of pulmonary functions.Results Compared with the normal control mice,the cigarette smoked mice have lower body weights (P＜0.05),enhanced inspiratory resistance (RI),and decreases on peak inspiratory flow (PIF),peak expiratory flow (PEF) and dynamic compliance (Cdyn) (P＜0.05).The total leucocyte numbers and the numbers of neutrophils,macrophagcs and lymphocytes in BALF were increased significantly in cigarette smoked mice which developed more severe lung inflammation and more mucus cells hyperplasia assessed by HE staining and PAS staining respectively.And higher levels of MUC5AC in BALF were found in cigarette smoked mice (P ＜ 0.01 vs control mice).Conclusions The COPD mouse model established with cigarette smoke mimics the clinical situations with similar pathological changes to the COPD patients and can be taken as an effective animal model for future COPD research.