The new model of nonalcoholic steatohepatitis in rats is based on alimentary effects of hypercaloric diet including much cholesterol and beef fat. This model reproduces structural and functional disorders in the liver, including hepatocyte fatty degeneration, parenchymatous necrosis and fibrosis paralleled by dyslipidemia and is intended for studies of the mechanisms of formation, progress, and therapy of liver diseases of noninfectious origin.