Using a commercial kit for the examination of recombinant immunoblot the authors examined sera of 85 patients with direct evidence of Borrelia burgdorferi sensu lato in serum or cerebrospinal fluid or patients with typical dermal form of borreliosis. The results were compared with results of assessment of specific antibodies by the ELISA test. The authors investigated the importance of antibody formation against different antigens in different clinical forms of the disease. The specificity of the investigated kit was higher than that of the ELISA test, the sensitivity was lower. Examination of the immunoblot was negative in 8.8% patients with direct evidence of the causal agent of Lyme borreliosis. A suitable configuration of the recombinant immunoblot for use in Europe where three genotypes of Borrelia burgdorferi sensu lato are found requires further investigation. Another problem are criteria for evaluation of positivity of the blot in Europe.