Miller Fisher's syndrome (MFS) commonly presents in the fourth and fifth decades and are rare in people over 70 years. An 85-year-old female with no significant medical history presented with upper extremity anesthesia, ptosis, and unsteady gait. The patient had a history of hypertension and diabetes mellitus. Physical examination showed bilateral total external ophthalmoplegia, areflexia, and cerebellar ataxia. Radiological and laboratory studies were unremarkable. Lumbar puncture showed albuminocytological dissociation. The combined history, physical examination, and lumbar puncture results established a presumptive diagnosis of MFS. Intravenous immunoglobulin was given for 5 days. The patient gradually improved 10 days after the onset of symptoms. Ophthalmoplegia had fully recovered after 6 months. To the best of our knowledge, this case represented the oldest patient with MFS.