Abstract: Objective　To investigate the roles of urotensin II (U-II) in rat with Chronic Obstructive Pulmonary Disease(COPD). Methods Male SD rats were randomly divided into chronic bronchitis group (group B), COPD group (group C), exsmoker group (group D) and control group (group A). The concentrations of U-II in plasma, BALF and lung tissues were measured by RIA. Lung function and pathological analysis of lung specimens were performed routinely. Results　There were no significant differences of plasma U-II levels in each groups. The BALF levels of U-II were 1.7, 2.2, 4.7, 4.9 folds higher than plasma levels in group A, B, C and D respectively (all P<0.01). The BALF levels of U-II from group B,C and D were 50%, 225%, 225% higher than those in group A respectively (all P<0.01).The lung tissue levels of U-II were also higher than those from the controls respectively (all P<0.05). The BALF levels of U-II correlated positively with the neutrophils counts in the BALF, with the pathological scores of airway inflammatory cell infiltrations, airway muscles and fibrous connective tissues proliferation (all P<0.01). There was a negative correlation between the BALF levels of U-II with the peak expiratory flow (P<0.01). Conclusion In the rat model of COPD, U-II levels in BALF and lung tissues were increased, indicating that it may act locally, or, via paracrin/autocrine way, play a role in the mechanism of the airway remodeling in COPD.