Shingles is a latent viral infection of the sensory ganglia. It can be accompanied by a variety of neurologic complications, including polyradiculitis and myelitis. A 66-year-old man with diabetes mellitus presented with progressive weakness, hypethesia and neuralgic pain in his right arm after herpes zoster infection in right C5 dermatome. He was diagnosed with zoster polyradiculomyelitis and treated with intravenous acyclovir and corticosteroid. It is a rare case of zoster neurologic complication in spite of oral acyclovir treatment.