The authors experienced a case of severe epistaxis caused by accidental partial middle turbinectomy during nasotracheal intubation, which the patient had bilateral concha bullosa narrowing the nasal airway. Although anesthesiologist checked nasal airway through subjective symptoms and the size of both nostrils, they tend to overlook common anatomic variation, concha bullosa, and can injure turbinate structures. Therefore, preoperative computed tomography images should be carefully evaluated for the possibility of concha bullosa, which narrows nasal airway and induces the traumatic injury or epistaxis during nasotracheal intubation.