Despite considerable achievements in the study of localized scleroderma, the etiology of the disease has not been investigated completely. Borrelia burgdorferi-the agent of Lyme disease-is suggested to be one of the possible etiological factors of localized scleroderma. However, among scientists, this hypothesis is quite controversial. We have conducted investigations of the level of IgM and IgG class antibodies to B. burgdorferi in the serum of patients with localized scleroderma. To rationally substantiate the role of B. burgdorferi in the occurrence of localized scleroderma, thirty-two patients with localized scleroderma treated at an in-patient department were examined. The level of anti-Borrelia antibodies was determined in ELISA. Diagnostic levels of IgM and/or IgG were detected in 18.8% of patients with localized scleroderma, which is more than in the population (p < 0.01). Positive levels of anti-Borrelia antibodies in patients with localized scleroderma confirm the borreliosis nature of the disease, requiring conduction of complex antimicrobial treatment.