Non-alcoholic fatty liver disease (NAFLD) comprises a range of chronic liver diseases from simple steatosis to steatohepatitis and cirrhosis with liver failure. In children, NAFLD is mainly associated with obesity and metabolic syndrome, the results of an unhealthy lifestyle. Insulin resistance and free fatty acids play a key role in the pathogenesis of NAFLD. NAFLD can therefore be seen as a metabolic complication of obesity. Since the prevalence of obesity in Dutch children is increasing, the prevalence of NAFLD in children is expected to increase as well. Prevention of obesity and identification of children with an increased risk of NAFLD are important steps in preventing irreversible liver damage. Lifestyle changes aimed at improving insulin sensitivity through healthy food and sufficient physical activity are essential in the treatment of NAFLD. Pharmacological treatment may have additional value.