A number of authors have called attention to the difficulty encountered in diagnosing tumors near the foramen magnum and have formulated symptom complexes in an effort to facilitate early recognition of these lesions. Emphasis has been placed on their bizarre symptoms and on their resemblance to the clinical picture associated with some degenerative diseases of the central nervous system, ruptured cervical disc and cervical spondylosis. Fortunately, it has been known that most of tumors around the foramen magnum are benign, extramedullary and amenable to cure by surgical excision and with minimal morbidity and mortality, provided they are diagnosed early. Recently we experienced a rare case of glioblastoma multiforme at the cervico-medullary junction. A 28-year-old Korean man was admitted to the Dept. of Neurosurgery on May 27, 1974, with 5 months history of cervical and suboccipital pain, and progressive visual disturbance. He had sustained hyperextension injury to his neck 8 months ago, and subsequently developed mild suboccipital and cervical pain which subsided easily with some analgesice. Three months later, he noticed paresthesia and tingling sensation in his upper limbs and anterior chest, especially when he turned his neck to either side. He also had pain in suboccipital region radiating to his both shoulders. Seven months later, he developed sudden paraperesis, poor vision and incoordination with severe suboccipital headache and vomiting. On admission, neurological examination disclosed clear consciousness, bilateral papilledema and abducens nerve palsy and markedly decreased vision. There were clumsiness of movement of both legs, hypesthesia in the face, decreased perception of vibration and position sense below the neck and increased deep tendon reflexes. Fine coordination movements in the upper limbs were disturbed and horizontal hystagmus was also present. Simple skull films showed destruction of the dorsum sellae and the posterior clinoid process, suggesting increased intracranial pressure. Cervical spine films were interpreted as normal. Right carotid angiograms demonstrated marked hydrocephalic patterns, and right vertebral angiograms demonstrated posterior displacement of the tip of the basilar artery and of the choroidal point. Conray ventriculogram showed a sharp filling defect at the level of lateral recess of the fourth ventricle. Suboccipital craniectomy and bilateral laminectomy of the first two cervical vertebrae were performed, disclosing a nodular, meaty, firm mass with some necrosis. The tumor was located posterolateral to the medulla and the spinal cord from the obex to the C2, compressing them and displacing the right cerebellar tonsil upward and laterally. The tumor was removed partially and Torkildsen's shunt was performed. Post-operatively he died suddenly at the end of the second week without any remarkable improvement in symptoms and signs. Pathological report was a glioblastoma multiforme. At autopsy, the tumor was originated from the cervicomedullary junction, extending posteriorly from the obex to the C2 and anteriorly along the brain stem up to the perichiasmatic region.