The authors report a case of acute spinal epidural hematoma occurring in a patient receiving antiplatelet drugs. A 76-year-old man with a history of cerebral infarction had been taking antiplatelet agents for one year. He suddenly developed severe back pain which woke him from sleep, and numbness of his lower extremities was then noted. He was hospitalized 15 hours later. Neurological examination revealed flaccid paralysis of both lower extremities with negative Babinski's reflex, and sensory disturbance below the level of L1. The bleeding time and prothrombin time were prolonged. Computed tomographic (CT) scan revealed a biconvex, relatively hyperdense mass in the posterior spinal canal at the level of T12. Metrizamide myelography disclosed an incomplete blockage caused by an epidural mass at the level of T11. Post-myelographic CT scan demonstrated a sharply demarcated extradural filling defect at the level of T11. Seventeen hours after the onset of symptoms, an emergency laminectomy was performed extending from T12 to L3, and the epidural clot was totally evacuated. Histological examination of the capsule of the hematoma revealed no vascular anomalies. The patient made a good postoperative recovery. To the authors' knowledge, this is the first reported case of spontaneous intraspinal hemorrhage in a patient taking antiplatelet drugs. Acute onset of persistent pain anywhere along the spinal axis and the development of spinal neurological deficits in a patient on antiplatelet therapy should raise the suspicion of a spinal epidural hematoma. It should be stressed that prompt neuroradiological diagnosis and rapid surgical decompression are essential to allow good recovery. The present case illustrates that neurological emergencies can occur in patients receiving antiplatelet therapy.