There are two types of common bile duct stones, namely primary and secondary common bile duct stones. Primary common bile duct stones are stones that originate in the extrahepatic bile duct and do not necessarily exist in the gallbladder. Secondary common bile duct stones are stones from the gallbladder that have drained into the common bile duct and are mostly of the same shape and nature as stones from the gallbladder. The pathological changes caused by either primary or secondary common bile duct stones depend mainly on the degree of bile duct obstruction caused by the stones and the occurrence of secondary infection. 1, severe cholangitis: this is the most serious complication of common bile duct stones, which is manifested by fever, abdominal pain, jaundice (commonly known as the triplet sign), and in severe cases, shock and psychiatric symptoms (commonly known as the quintuplet sign). At this time, if not timely and effective treatment, will be life-threatening. 2, biliary pancreatitis: if the common bile duct stone is embedded in the lower part of the common bile duct (jug abdomen) or obstructed in the duodenal papilla, it may lead to bile reflux into the glandular duct, secondary to acute pancreatitis, this complication is also one of the very critical complications, small stones in the gallbladder is the main cause of this complication, so small stones in the gallbladder need active surgical treatment. 3, biliary bleeding: stones repeatedly damage the mucosa of the bile duct wall causing bleeding, or in severe cases, damage the adjacent blood vessels around the bile duct wall to form pseudoaneurysms, which connect with the bile duct wall and hemorrhage occurs. 4, biliary cirrhosis: bile duct stones can cause repeated obstruction and infection of the bile duct, if not treated in time, it can cause continuous damage to hepatocytes, degeneration and necrosis of hepatocytes, fibrous tissue proliferation around the bile duct, and finally biliary cirrhosis. 5.Gastrointestinal biliary fistula: When the stone repeatedly damages the bile duct wall, erosion penetrates the bile duct wall and adjacent gastrointestinal, it will form a gastrointestinal biliary fistula.