Background and Objective The outcome of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is usually very poor, and it has been suggested that mechanical ventilation does not benefit AE-IPF patients. Noninvasive ventilation (NIV) has attracted attention as a means to avoid intubation in acute respiratory failure, including acute respiratory distress syndrome (ARDS). This study describes the outcome of patients with AE-IPF who were treated with NIV. Methods Patients included in the study were those who fulfilled the criteria for AE-IPF during the periods between April 1998 and June 2004 at Tosei General Hospital, and in whom NIV was introduced. Clinical data were obtained retrospectively from patient records. Results This study included 11 patients. The initial NIV settings were continuous positive airway pressure (CPAP) mode in 6 patients (mean 10.1±2.5 cmH2O) and Spontaneous/Timed mode in 5 (mean inspiratory positive airway pressure/expiratory positive airway pressure; 15.0±3.3/10.2±2.9 cmH2O). Five patients avoided intubation and survived more than 3 months after AE-IPF. Six patients who failed NIV died within 3 months. In these 6 patients, 4 required intubation. The other 2 patients, who refused endotrachial intubation, died without intubation. Median survival time and 3-month survivals after acute exacerbation were 30 days, and 45.5%, respectively. Conclusion Considering extremely poor prognosis of AE-IPF, our findings suggest that NIV is a viable option for the respiratory management in AE-IPF, and should be studied in a large, well-controlled trial.