Cholelithiasis is a disease in which stones occur in the biliary system, including the gallbladder and bile ducts. Its clinical manifestations depend on the location of the gallstones and on factors such as whether they cause obstruction and infection. Epidemiology. Gallstone disease is a common disease with a prevalence of about 0.9%-10.2% in China, with an average of 5.6%. It is significantly higher in women than in men, and increases with age. With the improvement of living standards and dietary hygiene, gallstones in China have changed from bile duct bile pigment stones to cholesterol stones in the gallbladder. There are many different types of gallstones, and there is no unified and perfect classification method. According to the composition, they are divided into bile pigment stones, cholesterol stones and mixed bile pigment and cholesterol stones. Depending on the location of the stones, they are classified as gallbladder stones, extrahepatic bile duct stones (common hepatic duct stones and common bile duct stones) and intrahepatic bile duct stones.