Fatty liver is not hepatitis. Fatty liver is the excessive deposition of fat in the liver. There are many etiologic factors including alcohol consumption and non-alcoholic factors, and non-alcoholic etiologic factors include poor lifestyles such as high-energy diets, sugary beverages, and sedentary lifestyle. Patients with diabetes, obesity, and metabolic syndrome are susceptible. Fatty liver usually has an insidious and slow onset and is often asymptomatic. A few may have symptoms such as fatigue, mild abdominal discomfort or distension. Steatohepatitis is a fatty degeneration of hepatocytes accompanied by inflammation, necrosis and fibrosis of hepatocytes. When fatty liver is combined with abnormal liver function, it is called steatohepatitis and requires prompt medical attention and targeted treatment under the guidance of a doctor.