Acute paraplegia attributable to disc herniation is known to occur most frequently at the thoracic level. A 50-year-old male presented with progressive limb weakness and hypoactive deep tendon reflexes. On the basis of clinical features and neurological findings, the diagnosis of Guillain-Barre syndrome was suspected. Spinal MRI showed cervical disc herniation. He underwent emergency surgery consisting of removal of herniated disc and anterior fusion. We emphasize that there is a possibility of acute progression of paralysis secondary to nontraumatic enlargement of cervical disc herniation.