A sudden onset of the syndrome Guillain-Barré in 48-year-old woman presenting as an acute motor neuropathy was associated with antibodies against ganglioside GM1 detected by ELISA. The neurological examination revealed flaccid quadriplegia without affection of the sensory system, and the additional investigation showed mild increase of the CSF protein content, demyelination of the peripheral motor nerves and significantly increased titer of the serum and CSF anti-GM1 antibodies. Several copruculture for Campylobacter jejuni gave negative results. There was a significant correlation between the severity of the clinical picture and the titer of the serum anti-GM1 antibodies. The patient completely and spontaneously recovered after five weeks. According to the clinical and laboratory parameters the patient could be classified as an axonal, and according to electromyographic findings and the course of the disease as the classical form of the syndrome Guillain-Barré.