A 37-year-old man involved in a motor vehicle accident was admitted to our hospital with disturbed consciousness. Computed tomography (CT) showed an acute, right-sided epidural hematoma and pneumocephalus. Emergency evacuation of the acute epidural hematoma was carried out, and his condition gradually recovered. However, cerebrospinal fluid (CSF) rhinorrhea continued despite conservative treatment. Three-dimensional reconstructed CT revealed a bone defect, which was approximately 20 mm in size, in the planum sphenoidale and tuberculum sellae, and magnetic resonance imaging demonstrated a traumatic meningo-encephalocele through the defect, with CSF collection in the sphenoid sinus. Endoscopic endonasal transsphenoidal surgery was performed. The 9-mm diameter dural defect was clearly visualized in the sphenoid sinus and was reconstructed with a combination of suturing and overlay with abdominal fascia, and absorbable polyglycolic acid felt. The CSF leakage from a traumatic meningo-encephalocele through the planum sphenoidale was successfully repaired by endoscopic endonasal surgery. Thorough preoperative evaluation of the feasibilities of the endoscopic and transcranial approaches should be based on the preoperative identification of the fistula, the bone defect, and vital structures.