An 81-year-old man presented with poor visual acuity of the left eye, swelling of the left eyelid, and elevation of the left intraocular pressure after contusion of the left palpebral portion. CT revealed left ocular proptosis and left intraorbital hematoma. Traumatic optic neuropathy was suspected, and emergent optic nerve decompression was performed through extradural anterior clinoidectomy followed by optic canal release. Postoperatively, his left visual acuity was markedly improved and the elevated intraocular pressure decreased. Postoperative CT demonstrated improvement of the left ocular proptosis and decompression of the optic nerve. Emergent optic canal release has been recommended in patients who have suffered visual dysfunction caused by optic canal fracture or intraorbital hematoma. The advantages of extradural anterior clinoidectomy followed by optic canal release include a shorter surgical route and easy identification of the optic nerve, resulting in fewer surgical complications. In addition, this procedure can achieve intraorbital decompression. We recommend extradural anterior clinoidectomy followed by optic canal release as a safe and reliable procedure for optic nerve decompression in patients with traumatic optic neuropathy.