Objective　To discuss the values of fiber bronchoscopy with three-way laryngeal mask airway continuous ventilation in 1-6 month old infants with oxygen-dependent respiratory diseases. Methods　From January 2010 to May 2011, 29 cases of 1-6 month old infants with oxygen-dependent respiratory diseases who underwent conventional fiber bronchoscope and 148 cases of 1-6 month old infants with oxygen-dependent respiratory diseases who underwent fiber bronchoscopy with threeway laryngeal mask airway continuous ventilation were enrolled in control and treatment groups respectively. The success rate of fiber bronchoscope and the incidence rate of complications were compared between two groups. Results　In the treatment group, the success rate of fiber bronchoscope was 89.2% which was significantly higher than 58.6% in the control group and the rate of laryngeal edema was 9.1% which was significantly lower than 35.3% in the control group. The rates of endotracheal intubation ventilation and postoperative hemorrhage were lower than those in the control group, but the difference was not statistical ly significant. Conclusion　Fiber bronchoscopy with three-way laryngeal mask airway continuous ventilation is superior to the traditional fiber bronchoscope in 1-6 month old infants with oxygen dependent respiratory system diseases.