Protein biosynthesis was markedly altered in liver cells after acute and chronic administration of ethanol in vivo and in vitro. The effects were dose- and time-dependent. Synthesis of cytoplasmic and nuclear proteins was inhibited in hepatocytes. In chronic intoxication activity of fibroblasts and collagen synthesis were stimulated. The data obtained suggest that inhibition of amino acids activation, impairment of translation and transcription were involved in mechanisms of the ethanol toxic effects on liver tissue. At the same time, negative effects of ethanol and its metabolites appear to be related to post-translation modification of polypeptides.