Demyelinating neuropathy is considered a rare complication of Lyme borreliosis. We report a case of meningoradiculitis due to Borrelia burgdorferi in which the neurophysiological analysis showed evidence of restricted demyelinating involvement of the nerve roots and plexus, with no peripheral involvement or signs of distal axonal lesions. Lyme disease, therefore, can in fact be associated with demyelinating polyradiculitis with no peripheral nerve damage.