Introduction Implementation in practice of new highly informative immunologic tests allowed diagnosis of latent tuberculosis infection. Nevertheless nowadays no reliable immunologic criteria exist to distinguish active tuberculosis and latent tuberculosis infection. Objective To evaluate differences in levels of specific immunoglobulins in subjects with active lung tuberculosis and in subjects with latent tuberculosis infection. Materials and methods Within 2015-2017 in Institute of Phthisiopulmonology we examined 50 subjects with lung TB with bacterial excretion (I group) and 15 subjects with latent TB infection (II group). Diagnostic complex included ELISPOT and Diaskintest, assessment of clinical symptoms, X-ray, and bacteriological methods, evaluation of immune complexes stimulated by specific antigen ESAT-6/SFP-10 comprising of IgE, IgG3, IgG1, IgG1 + IgG3, IgG1 + IgE (by method of dynamic light dispersion). Statistical analysis was done by program Statistica 7.0. Criterion of chi-square (χ2) was applied. Distinctions were considered significant at р<0.05. Results In the both groups ELISPOT and Diaskintest were positive. We have statistically significant differences in the level of specific immunoglobulins in the groups. Immune complexes were identified in all patients with TB (7.25±0.34 vs. 2,28±0.23, p0.01), of IgG1 (4,3±0.25 vs 2.38±0.12, p0.01), IgG3 (3.2±0.37 vs 2.0±0.12, p0.01), IgE (3.48±0.25 vs 0.2±0.02, p0.001), IgG1+IgG3 (4.08±0.24 vs 2.5±0.02, p0.01), IgG1+E (7.72±0.22 vs 6.3±0.12, p0.01), IgG3+E (7.15±0.32 vs 0, p0.001) were identified. Conclusion. The most significant differences were observed in levels of specific immunoglobulins, immune complexes, IgG3, IgE, as well as their isotypes, that may be used as criteria to differentiate between active tuberculosis and latent tuberculosis infection.