Objective To detect sputum quantitative bacterial culture and sputum cell counts in stable chro -nic obstructive pulmonary disease (SCOPD) patients, and explore the correlation between lower airway bacterial colo-nization(LABC) and airway inflammation.Methods 47 patients with SCOPD were chosen ,all patients induced spu-tum specimens to sputum quantitative bacterial culture and sputum cell counts ,sputum and serum IL-8 levels were al-so detected.Results There were 13 patients whose bacterial colonization of the lower respiratory tract in patients was higher than 107CFU/mL.Serum IL-8 levels of 13 patients was ( 70.65 ±19.89 ) pg/mL, sputum IL-8 levels was (364.65 ±74.19)pg/mL,all significantly higher than those whose bacterial colonization of the lower respiratory tract lower than 107CFU/mL,(15.87 ±3.01)pg/mL and (146.65 ±28.11)pg/mL,there were statistically significant difference(t=13.43,9.76,all P<0.05).After 1-year follow-up,FEV1 decline(0.071 ±0.016)L in patients whose bacterial colonization of the lower respiratory tract≥107CFU/mL,it was significantly higher than those whose bacterial colonization of the lower respiratory tract <107CFU/mL;the frequency of acute exacerbation was (2.93 ±1.07) times,significantly more than those whose bacterial colonization of the lower respiratory tract <107CFU/mL,the differ-ences were statistically significant (t=5.43,6.54,all P<0.05).Conclusion Lower respiratory tract bacterial colo-nization in patients with SCOPD can aggravate the inflammatory response and increase degree of airflow limitation .