Summary. The purpose of the study is to comparison of methods for diagnosing the state of the respiratory organ of experimental animals under the influence of physical factors, the intensity and exposure times of which are close to extreme. Materials and methods of research. The experiments used 45 male rabbits of the “Soviet Chinchilla” breed with a body weight of 2,7-3,4 kg, randomly divided into a control group, a group exposed to the lungs, a group exposed to the hearing organ and a group exposed to thermal effects on different areas of skin. To differentiate structural and functional disorders of the external respiratory system, three methods for diagnosing the state of the respiratory organ of experimental animals (rabbits) were used: acoustic impedance measurement of the respiratory tract, analysis of biophysical parameters of the lungs and pathological examination. A general conclusion about the state of the respiratory organ was given on the basis of a comparative statistical analysis of the characteristics of animals in the experimental and control groups. The relative size of the area of hemorrhages on the pleural surface of the lungs was used as a criterion indicator. The results of the study and their analysis. It has been shown that methods for diagnosing the state of the respiratory system based on impedance, biophysical indicators and the results of a pathological examination complement each other, providing an objective diagnosis of the state of the respiratory organ of experimental animals under the influence of physical factors, the intensity and exposure times of which are close to extreme, and are comparable in objectivity (sensitivity and diagnostic specificity) with methods used in medical clinical practice (impulse oscillometry).