To specify differential and diagnostic criteria of hemodynamic and non-hemodynamic pulmonary edema, canine experimental simulation (15 trials) of different types of abnormal hemodynamic and lung capillary permeability parameters was carried out. The X-ray pictures of 71 patients with and acute diffuse lesion of the pulmonary vascular channel (including 51 with adult respiratory distress and 20 with hemodynamic pulmonary edema) was analysed. The findings substantiated the possibility of making a differential diagnosis of pulmonary edema of various genesis. Symptom complexes, typical of predominantly higher permeability of the lung capillaries and hemodynamic disturbance, were formulated.