Abstract: OBJECTIVE To explore the risk factors for pulmonary infections in patients with chronic obstructive pulmonary diseases (COPD) and investigate the changes of levels of serum inflammatory factors. METHODS A total of 72 COPD patients who were treated in hospitals from Mar 2016 to Mar 2017 were recruited as the study objects.The univariate analysis and multivariate logistic regression analysis were performed for the risk factors for the pulmonary infections; the changes of levels of serum interleukins (IL-1 β, IL-4, IL-6, IL-8, IL-10), tumor necrosis factors (TNF-α, TNF-β) and interferons (IFN-α,IFN-γ) were observed. RESULTS Of the 72 COPD patients, 33 had pulmonary infections, with the infections rate 45.83%.The multivariate analysis indicated that the advanced age, long length of hospital stay, multiple types of complications, abuse of antibiotics and mechanical ventilation were the independent risk factors for the pulmonary infections in the COPD patients.The levels of IL-1β, IL-4, IL-6, IL-8 and IL-10 of the patients with pulmonary infections were significantly higher than those of the patients without pulmonary infections (P＜0.05).There was significant difference in the level of TNF-α, TNF-β, IFN-α or IFN-γ between the patients with pulmonary infections and the patients without pulmonary infections (P＜0.05). CONCLUSION The major risk factors for the pulmonary infections in the COPC patients include the advanced age, long length of hospital stay, more than two types of complications, abuse of antibiotics and mechanical ventilation.There is significant change in the level of interleukins, tumor necrosis factors or interferons of the patients with the infection.It is of great significance to reasonably use antibiotics for the COPD patients with the high-risk factors based on the results of microbiological surveillance and drug susceptibility testing, shorten the mechanical ventilation duration and detect the levels of serum inflammatory factors so as to facilitate the diagnosis and treatment of the patients with pulmonary infections.