Endoscopic surgery for choledochal stones can take anywhere from less than 1 hour to 5 hours, depending on the difficulty of the procedure. If the procedure is simple, it may take less than an hour; if it is complex, it will inevitably take longer and may even require multiple surgeries. Extrahepatic bile duct stones can be treated by choledochotomy, choledochoscopic stone extraction, or endoscopic ERCP, which takes less time. Intrahepatic bile duct stones will cause lesions such as bile duct stenosis in addition to stones, which makes the surgery more difficult and prolongs the time. To summarize, the length of the operation time depends on the difficulty of the operation, before the operation, we must do a good job in the preoperative examination and other preparations, in the operation must be carefully operated to avoid accidents.