ENBD is done by passing the nasobiliary tube through the duodenoscope during ERCP consultation, inserting the curved end into the appropriate part of the bile duct through the duodenal papilla, and the remaining part is drained along the duodenum, stomach, esophagus, pharynx, and mouth, and finally borrowing a nasal catheter and draining it out of the nostril, fixing it in the cheek, and receiving a sterile drainage bag to fix it, and after fixing it, you can see the bile flow of various nature. This drainage method is called endoscopic nasobiliary drainage, and its main purpose is to establish drainage, relieve obstruction, reduce biliary pressure, and prevent infection.ENBD is a treatment based on ERCP, which is simple and safe, and has important clinical significance, such as the observation of bile, culture of bile, and even the examination of exfoliative cytology, which can be more helpful for the diagnosis of some diseases in the biliary tract.