Objective To investigate the causes and influence factors of fungous infection pneumonia. Methods A total of 96 patients admitted by our hospital from Jan 2000 to Dec 2004 with fungous infection pneumonia were retrospectively analyzed. Results All pulmonary fungous infection patients, aged 78 years in average, had severe basic diseases and employed polyantibiotics. The risk factors included abusive usage of antibiotics and polyantibiotic, immunosuppression and malnutrition. Blastomyces albicans was the main pathogen in the infection of pulmonary fungus. Conclusion The main risk factor of hospital acquired fungous infection pneumonia is abusive usage of antibacterial and the existence of the basic diseases.