A 23-year-old female presented with chronic occipitalgia without signs of increased intracranial pressure followed by worsening headache and slight gait unsteadiness. Cerebral magnetic resonance (MR) imaging showed no corresponding lesions. Cervical MR imaging revealed a cervical intramedullary tumor. Intraoperatively the subpial tumor was found to stretch the 3rd-5th dorsal nerve roots posteriorly, which was thought to cause the intolerable headache. Total tumor resection was achieved without requiring myelotomy using electrophysiological monitoring with somatosensory and motor evoked potentials. Histological examination identified diffuse astrocytoma. Postoperatively the headache had completely resolved. Cervical astrocytoma of subpial location is a very rare cause of headache in adults. The subpial location enables surgical extirpation because minimal or no myelotomy is needed.