The pneumosclerosis develops in lungs of a connecting tissue as an outcome nonspecific (pneumonias, bronchites) or specific (a tuberculosis, a lues) inflammatory process, and also pneumoconiosises, long stagnation in a small circle of a circulation (a mitral stenosis, other illnesses of heart), immune allergic vasculites. Formation of a connecting tissue occurs cellular by, less often without participation of cells (hyalinosis). Signs are characteristic localization in sites of a carnification of not resolved pneumonia, on a course of outflow of a lymph from the centers of an inflammation, around of lymphatic vessels, in interalveolar septums, in a perivascular tissue, emptiness of capillaries and a reduction of a capillary bed, current depend on a basic disease at which exacerbations the pneumosclerosis progresses also. Gradually the respiratory surface of a lung decreases, the emphysema develops, there is a reorganization of a pulmonary tissue to formation of bronchiectasias, there is a difficulty of a circulation in a small circle with formation of a pulmonary hypertensia. Set of these changes name a pneumocirrhosis.