Background. Despite the progress and development of scientific directions in various fields of medicine, the problem of tuberculosis and its morphological manifestations remains relevant and is not fully disclosed due to complex pathogenesis, the presence of various clinical forms, therapeutic pathomorphosis, torpid to therapy, the presence of relapses. It is known that a surfactant system occupies a special place in the system of local lung protection.Aim. To study the condition of surfactant-assotiated protein A in the foci of specific destruction and in the surrounding intact lung tissue to assess its functional status, degree of respiratory failure and possible dissemination of tuberculous inflammation.Material and Metods. An analysis of 163 lung fragments of the dead or operated on for cavernous pulmonary tuberculosis with active bacterial excretion of 89 fragments and with clinical abacilation – 74 was carried out. Results A morphological study revealed stereotypical dynamic depression of surfactant-associated protein A in all the samples studied, both in the areas of cavernous destruction and pericavernouse zone, and in intact lung tissue. The maximum intensivity of the immunohistochemical expression of this surfactant protein was recorded in the alveolar macrophages, which indicated intensive recycling and utilization of the components of the surfactant.Conclusion. Minimizing the production of surfactant components and its active utilization in intact lung tissue leads to a collapse of the alveoli with subsequent progression of respiratory failure.