A total of 54 patients with tick-borne annular erythema (TAE) were investigated. In 41 patients different nervous system involvement signs were observed: radicular syndrome, serose meningitis, limbs paresis. Epidemiological and clinical signs of TAE in the USSR are much like those of Laim disease in USA and Western Europe. Laboratory investigations that were performed in 13 TAE patients have detected antibodies to the infecting agent of the Laim disease in 8. Treatment with broad spectrum antibiotics had a beneficial effect in these cases.