Diagnosis of Lyme disease is often problematic. Atypical clinical symptoms and diversified immunological response to the various Borrelia burgdorferi species present in the environment cause difficulties in a correct diagnosis. Hence the importance of using diagnostic methods least significantly affected by false positive and false negative results. The comparison of results achieved with ELISA test kit and two different Western blot test kits shows a considerable number of false positive and false negative results. The total conformity of ELISA test and Western blot tests results in our study was 65.6% (IgM ELISA: Mikrogen), 69.8% (IgM ELISA: Viramed), 83.9% (IgG ELISA: Mikrogen), 81.9% (IgG ELISA: Viramed). Higher conformity was observed in results for IgG antibodies. However, for IgM antibodies 11.45% (Mikrogen) and 13.5% (Viramed) of negative results achieved with ELISA test kit were indicated as positive using Western blot test kits. Despite the use of a very sensitive screening test, a considerable amount of false negative results was obtained. Such a situation is concerning in a two-step diagnostic procedure where only positive and equivocal results are further confirmed by Western blot method. The obtained results have demonstrated that ELISA test kit used in this study is not sensitive enough to be used as a screening test. The divergences obtained in Western blot tests results may be caused by the differences in the composition of each test and the differences in the methods of deriving antigens.