ObjectiveTo evaluate the risk factors for secondary pulmonary fungal infection in patients with chronic obstructive pulmonary disease (COPD).MethodsClinical data of 52 cases of secondary pulmonary fungal infection associated with COPD were analyzed retrospectively through casecontrol study , 52 cases of COPD patients without secondary pulmonary fungal infection were randomly selected as control, and risk factors were analyzed．ResultsFungi which isolated from 52 infected patients included Candida albicans(40 cases, 76.92%), Candida glabrata(3 cases, 5.77%), Candida tropicalis(7 cases, 13.46%), Mucor(1 case， 1.92%), and Aspergillus(1 case， 1.92%) . Univariate analysis showed that the factors associated with secondary pulmonary fungal infection included duration of broadspectrum antimicrobial use>14 d, cumulative amount of systemic glucocorticoid use >500 mg, hypoalbuminemia, typeⅡrespiratory failure, mechanical ventilation and diabetes mellitus. Multivariate Logistic regression analysis showed that cumulative amount of systemic glucocorticoid use >500 mg, duration of broadspectrum antimicrobial use >14 d, mechanical ventilation and typeⅡrespiratory failure were high risk factors for secondary pulmonary fungal infection in patients with COPD.ConclusionThe knowledge of the risk factors for secondary pulmonary fungal infection associated with COPD can promote to take proper preventive measures, and reduce the occurrence of deep fungal infection .