A Le Fort I osteotomy is a common procedure for correcting dental and facial deformities in orthognathic surgery. In rare cases, a delayed hemorrhage can occur as early as several hours or up to 12 weeks, postoperatively. The most frequently involved blood vessels in a delayed hemorrhage are the descending palatine artery, the internal maxillary artery, and the pterygoid venous plexus of veins. Intraoral bleeding accompanied by severe epistaxis in these cases makes it difficult to locate the precise bleeding focus. Eventual uncontrolled bleeding would require Merocel packing or surgical intervention. In general, a severe late postoperative hemorrhage is most effectively managed by angiography and embolization. Herein we describe a delayed hemorrhage case in which the cause was not evident on angiography. We were able to detect the bleeding point through an endoscopic nasal approach and treat it using direct cauterization.