The pathogenesis of non-alcoholic steatohepatitis (NASH) has not been fully studied yet. At the same time, some key points of its forming are already clear. In this regard, the authors studied disturbances of carbohydrate and lipid metabolism in patients with NASH. This included evaluation of fatty acid (FA) and lipoprotein (LP) spectrum, as well as measurement of triglyceride (TG), malonic aldehyde and glucose blood concentrations. The study found that an important role in the pathogenesis of NASH is played by carbohydrate and lipid dysmetabolism, manifested by hyperglycemia, glucose tolerance disorder, and type II diabetes. Other manifestations include hyperlipoperoxidcholia, high concentrations of chylomicrons, low density lipoproteins, and triglycerides, as well as low concentration of high-density lipoproteins. The spectrum of higher fatty acids is characterized by high concentration of saturated fatty acids and deficit of polyunsaturated fatty acids.