Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases and the hepatic manifestation of metabolic syndrome. Obesity is present in 60-95% of patients with NAFLD. The pathogenic eRect of obesity is based on the increased metabolic activity of intra-abdominal adipose tissue releasing larger amounts of free fatty acids due to greater density of mitochondria and consequently higher levels of lipolysis and glycolysis. In addition, visceral adipose tissue functions as an endocrine organ and participates in the secretion of numerous adipocytokines, primarily numerous proinUammatory cytokines, which contribute to metabolic disorders. The majority of patients are asymptomatic, except in rare cases when fatigue, with or without alterations of liver enzymes, occurs. Treatment involves weight loss by changing lifestyle and exercising regularly. For now, there is no eRective pharmacological therapy although there are numerous ongoing studies, including the administration of vitamin D. Intragastric balloon placement and bariatric surgery, with previous dietetic restrictions, should also be considered in the treatment. Relation between obesity and NAFLD also implicates the development of liver cirrhosis, in addition to other risk factors of obesity, as well as the development of hepatocellular carcinoma.