Background: Fractures of the orbital roof not associated with fractures of the orbital rim are unusual. We describe the case of a blowout fracture of the orbital roof with an intact orbital rim, which was found after craniotomy for removal of epidural hematoma. Case: A 64-year-old man was referred to our emergency department from a local hospital. He fell down from a 3-m stepladder while pruning branches of a tree. Brain computed tomographic scan revealed acute epidural hematoma in both frontal convexities, and he underwent craniotomy at the local hospital. On follow-up brain computed tomography, an orbital roof fracture with a displaced bony fragment and hemorrhage was noticed in the left superior extraconal space. Thereafter, he was transferred to our department. Upon examination, movement of the extraocular muscles was normal. He did not complain of diplopia or decreased sensation of the face. He also did not have nasal stuffiness. Exophthalmometry revealed the same findings for both eyes (18 mm/18 mm). Facial computed tomographic scan before the second operation revealed a displaced orbital roof fracture segment. Under general anesthesia, craniotomy was performed and the epidural hematoma was evacuated. The displaced bony fragment was removed from the left anterior cranial fossa, and the anterior skull base was reconstructed with a titanium mesh plate. Conclusion: Through this case of blowout fracture of the orbital roof with an intact orbital rim, found after craniotomy, we should be aware of the possibility that an orbital roof fracture can be missed on conventional brain computed tomography.