Objective To investigate the clinical value of bronchofibroscope to the patients with respiratory failure treated by mechanical ventilation. Methods 44 patients with respiratory failure treated by mechanical venti-lation who were rescued with bronchofibroscope in EICU from January 2006 to June 2007 were compared the days of antibiotic application, the days of mechanical ventilation and mortality rate with 35 patients with respiratory failure treated by mechanical ventilation but not using bronchofibroscope during January 2005 to January 2006. Results Compared with the control group, the therapy group had fewer days of antibiotic application, fewer days of mechani-cal ventilation and lower mortality rate(P < 0.05). During absorbing expectoration with bronchofibroscope, compli-cation such as haemorrhage did not happen. Conclusion Bronchofibroscope application in the patients with respira-tory failure treated by mechanical ventilation can shorten the time of mechanical ventilation and cut down the mortal-ity rate,which was worth generalizing in clinical work.