Idiopathic subglottic stenosis (ISS) is defined as the narrowing of the upper airway without any known cause. A 40-year-old female was referred to our hospital with the complaint of exacerbation of dyspnea causing difficulty in going out. Chest computed tomography (CT) scan and bronchoscopy revealed subglottic tracheal stenosis with a luminal diameter of 5 mm at the narrowest part. Tracheal mucosa of the stenotic lesion was smooth, and the patient had no previous medical history. Subglottic tracheal resection of the stenotic lesion and reconstruction were performed. The postoperative course was good, and the symptom of dyspnea improved significantly. Recently, some reports have suggested conservative treatments such as laser and balloon dilation for ISS, but the recurrence rate after these treatments is still high. Surgery is recommended rather than conservative treatments for patients with less severe inflammation of tracheal mucosa and other comorbidities like present case.