Objective To analyze the clinical features,risk factors and etiological conditions of pulmonary fungal infection in patients with severe pulmonary infections. Methods A retrospective analysis was performed on 182 critically patients with severe pulmonary infections who met the inclusion criteria in the department of respiratory and critical care medicine of affiliated hospital of Inner Mongolia Medical University from January 2019 to December 2023, including 90 patients with pulmonary fungal infection （confirmed and clinically diagnosed） and 92 patients in a control group. General data,clinical features,imaging changes, etiological data of the patients were summarized and analyzed,and risk factors affecting pulmonary fungal infection were analyzed by Logistic multivariate regression. Results （1）The clinical manifestations of severe patients after fungal infection were mainly cough, sputum, dyspnea, fever, pulmonary rales, and hemoptysis, which were not significantly different from those of the control group.（2） The specimen sources were as follows. Two confirmed patients were diagnosed by bronchoscopic biopsy. Of the 88 clinically diagnosed cases, 65 cases were detected by sputum culture,12 by bronchoalveolar lavage fluid culture, and 11 by sputum culture combined with blood G test and GM test. Among the infected patients. Among the infected patients, 83 cases （92.2%） were detected with one kind of fungus, among which candida albicans was the most detected, followed by Aspergillus,and 7 cases （7.8%） were infected with two kinds of fungi. （3） Multivariate Logistic analysis showed that chronic obstructive pulmonary disease, mechanical ventilation, central venous catheter, duration of glucocorticoid use, duration of broad-spectrum antibiotic use,and hypoproteinemia were independent risk factors for pulmonary fungal infection. （4） ROC curve analysis showed that the AUC value of chronic obstructive pulmonary disease, mechanical ventilation, central venous catheter, duration of glucocorticoid use, duration of broad-spectrum antibiotic use and hypoproteinemia combined to predict pulmonary fungal infection was 0.92, which had a good predictive value. Conclusions Chronic obstructive pulmonary disease, central venous catheter, mechanical ventilation, duration of glucocorticoid use, duration of broad-spectrum antibiotic use and hypoproteinemia are independent risk factors for pulmonary fungal infection in patients with severe pulmonary infections,and the combined value of all the factors is better in predicting the pulmonary fungal infection.