Myocardial and skeletal muscle impairment caused by alcohol has been thoroughly studied. Nevertheless, the simultaneous involvement of those tissues by ethanol has not been broached in medical literature. We have studied ten patients undergoing alcoholic cardiomyopathy. They were subjected to a detailed neurological examination, muscle enzymes serum level determinations, electromyography, and muscle biopsy with analysis of the tissue by usual histological techniques and by electron microscopy. Only one of ten patients exhibited proximal weakness and atrophy of the lower limbs, the electromyographic and histological findings correlating with the clinical feature of the chronic muscle disease due to alcohol consumption. The electromyographic findings included muscle disease in eight patients, neuron disease in one patient and no changes at all in the tenth patient. In one patient only, the skeletal muscle proved normal when examined by conventional histological techniques. In the other nine patients there were several minimal changes, such as the proliferation of nuclei beneath the sarcolemma, atrophy of fibers, hyalinisation, vacuolation, loss of muscle fiber striae, and atrophy of groups of fibers. Electron microscopy demonstrated the following changes in nine patients: intracellular edema, dissociation of myofilaments, alteration of the Z line, changing in the shape and increase in the number of mitochondriae, thickening of sarcolemma, and vacuolation and increase of the glycogen granules. Since all patients exhibited skeletal muscle injury, we concluded that there is a close relation between alcoholic cardiomyopathy and skeletal muscle disease.