Abstract: OBJECTIVE: To understand the clinical characteristics, strain distribution and treatment regression of lower respiratory tract fungal infections in mechanically ventilated patients in the emergency intensive care unit (EICU). METHODS: To retrospectively analyze the clinical data of patients with lower respiratory tract fungal infections occurred in the EICU of Xinhua Hospital from October 2007 to December 2008 by mechanical ventilation. RESULTS: Lower respiratory tract infections occurred in 80 of 124 mechanically ventilated patients, with an incidence of 64.5%, including 21 cases (26.2%) with fungal infections, all of which were Pseudomonas spp. (11 cases of Pseudomonas albicans, 5 cases of Pseudomonas tropicalis, 3 cases of Pseudomonas smoothus, and 2 cases of Pseudomonas subsmoothus); Apache II score for fungal infections compared with non-fungal infections. 21.89 vs 17.36, mean mechanical ventilation: (20.5 vs 14.2) d, length of ICU stay: (22.5 vs 18.4) d, mortality: 33.3% vs 15.2%, all higher than non-fungal infection cases; 11 cases of Pseudomonas albicans without 1 death and 7 cases of non-Pseudomonas albicans deaths. CONCLUSION: The incidence of concomitant lower respiratory tract fungal infections in mechanically ventilated patients in EICU is high, mainly Pseudomonas aeruginosa infections, with Pseudomonas albicans predominating. In contrast, non-Pseudomonas albicans infections have a high morbidity and mortality rate and are resistant to fluconazole, suggesting that effective interventions should be taken early.