ERCP is the initials of Endoscopic Retrograde Cholangio-Pancreatography (ERCP), which is an endoscopic technique of injecting contrast agent through the duodenal papilla to retrograde the pancreaticobiliary duct, and is currently recognized as the gold standard for diagnosing biliopancreatic duct diseases. With the development of minimally invasive technology, ERCP is now the preferred minimally invasive technique for the treatment of benign and malignant biliopancreatic diseases such as biliopancreatic duct stones, tumors, biliopancreatic stenosis, obstructive jaundice, etc. The procedure: Transendoscopic retrograde cholangiopancreatography is to insert a fiberoptic duodenoscope into the descending duodenum, find the large duodenal papilla (hereinafter referred to as the papilla), insert a plastic catheter into the biopsy duct to the opening of the papilla, inject a contrast agent and then take an X-ray to show the pancreaticobiliary duct. Endoscopic nasal bile drainage (ENBD), endoscopic internal bile drainage (ERBD), lithotripsy, stent placement and other interventions. Advantages: no surgical incision on the body surface, less trauma, shorter hospital stay, faster recovery, lower cost than traditional surgery, popular among patients. Indications: 1.Obstructive jaundice of unknown origin suspected to have extrahepatic biliary obstruction. 2, suspected of various biliary tract diseases such as stones, tumors, sclerosing cholangitis, etc. with unknown diagnosis. 3.Suspected congenital biliary tract abnormalities or recurrence of symptoms after gallbladder surgery. 4.Pancreatic diseases: pancreatic tumor, chronic pancreatitis, pancreatic cyst, etc. Of course, there are risks associated with any procedure, and ERCP-related risks include acute pancreatitis, papillary injury, bleeding, perforation, etc. However, these complications are generally mild and can be improved with symptomatic treatment, but there are individual patients with more severe complications, which are closely related to the patient’s own anatomy, general physical condition, and time of consultation.