OBJECTIVE To explore the role of monocyte chemoattractant protein-1 (MCP-1) in the pathogenesis of chronic obstructive plumonary disease (COPD). METHODS Rat COPD model was established by exposing the rats to cigarette smoke daily. After COPD model was set up, bronchoalveolar lavage was performed. Total cell counts and alveolar macrophage (AM) counts in bronchoalveolar lavage fluid (BALF) were examined and the levels of MCP-1 and tumor necrosis factor-alpha (TNF-alpha) in BALF and serum were measured by ELISA. Lung tissue sections stained by HE were measured in terms of MLI, MAN and PAA by picture analysis system. RESULTS MLI and PAA in COPD model were higher than those of control group while MAN was just on the contrary. Except MCP-1 levels in serum [(32.75 +/- 10.91) pg/ml vs (24.13 +/- 6.92) pg/ml, P>0.05], MCP-1 levels, TNF-alpha levels, total cell counts and AM counts in BALF of COPD model group were significantly higher than those of control group (P<0.01). Positive correlations were demonstrated among MCP-1 levels, TNF-alpha levels and AM counts in BALF in COPD group, but were not demonstrated between MCP-1 levels, TNF-alpha levels in serum and AM counts. CONCLUSION There is a close correlation between MCP-1 in BALF and airway inflammation in COPD.