The myocardium of both heart ventricles in acute (AAP) and chronic (CAP) alcoholic poisoning was studied in 90 randombred rats. Functional-morphological changes typical of alcoholic cardiomyodystrophy were shown to develop in the heart in AAP and CAP. In AAP, alcoholic cardiomyodystrophy may lead to acute cardiac insufficiency and in CAP to progressive reduction of the contractile function of the heart and disturbances of conductivity in it. In AAP, however, the leading factor is the disturbance of bioenergetics as a result of toxic effect of ethanol and its metabolites on mitochondrial membranes under conditions of markedly disordered microcirculation. In CAP, along disordered microcirculation. In CAP, along with compensatory-adaptative processes in cardiomyocytes there increase the defects of the contractile apparatus, and diffuse fine-focal cardiosclerosis. This is the result of a long-term effect of ethanol and progressive hypoxia due to the affected vessels and disorders in lipid metabolism. Disorders in the function of sarcoplasmic reticulum may contribute to reduced contractile capacity of the heart.