A 23-day-old infant referred to the neonatal intensive care unit with difficulty breathing and inspiratory stridor increasing with exercise. Medical history included a cardiothoracic surgery for transposition of the great arteries, patent ductus arteriosus, atrial septal defect, and a history of intensive care unit from surgery. Flexible fiberoptic transnasal laryngoscopy revealed subglottic stenosis that was probably caused by prolonged intubation with a higher airway pressure. Computed tomographic scan of the neck showed a tiny stenosis without cartilage deformity and limited in subglottic region. Tracheotomy and external open surgery was found risky for sternal wound infection or mediastinitis as the neonate had newly thoracotomy. The patient had a balloon dilation under general anesthesia without intubation. Presenting symptoms of the neonate were fully improved with balloon dilation.