A case of acute aortic dissection (AAD) presenting as sudden, transient paraplegia and severe back pain is reported. The patient was a 66-year-old male with a 10-year-history of hypertension. The pain characteristically migrated from the back to the neck and then returned to the back. He showed complete transverse myelopathy at the level of the 9th thoracic cord. Computed tomography disclosed internal displacement of aortic intimal calcifications, without abnormalities in the spinal canal, and myelography showed no spinal canal block or stenosis. Electrocardiography and chest x-ray indicated nonspecific changes of high amplitudes and mild cardiomegaly, respectively. Together, these findings suggested acute aortic dissection with spinal cord ischemia. The initial systolic blood pressure of 220 mmHg was lowered with medication, and the pain was controlled with morphine. He recovered fully and was discharged 80 days after the onset of symptoms, with no neurological deficits. AAD carries a very poor prognosis unless treated immediately. Therefore, it is very important to promptly differentiate this disorder from spinal vascular conditions that also produce back pain and paraparesis.