An analysis of roentgenograms of 50 patients with a respiratory distress-syndrome has shown that roentgenosemiotics of this complication discloses alterations of permeability of pulmonary and bronchial capillaries, drainage of liquid from the interstice and alveoli, hemodynamics in the microcirculation link of the lesser circulation circle. A classification of the respiratory distress-syndrome is proposed which includes 3 stages and a period of involution of the process.