Clinical and laboratory data are available on affection of the peripheral nervous system (PNS) in 27 patients with Lyme-borreliosis (LB) in the endemic region of Russia. PNS disorders arose early, 88.9% of the patients had them within one month of the disease. 9 (37.5%) patients had meningoradiculoneuropathy (MRN) which emerged in the acute period in 77.8% of the patients. Inflammation in the cerebrospinal fluid was registered only in patients with clinical signs of meningitis. MRN developed more frequently in facial nerve neuritis (FNN) than in radiculopathy (RP)-80.0% and 14.3%, respectively, p = 0.01. Intrathecal synthesis of antibodies to B. burgdorferi in combination with pleocytosis was found only in FNN patients (16.7%). In 6 (37.5%) of 16 patients with neuroborreliosis concentrations of C-reactive protein were elevated. Its high level occurred significantly more frequently in RP (83%) than in FNN (17%) (p = 0.05). 5 out of 14 LB patients exhibited high level of Willebrand factor antigen. No clear clinical relations between this value and PNS lesions in LB were found.