I. Overview Biliary complications are a common problem after liver transplantation. The incidence of biliary complications has been inconsistently reported, with the overall incidence generally ranging from 7% to 34%. Recent advances in surgical techniques, organ preservation and immunosuppression have resulted in donor liver survival rates of more than 80% in most transplantation centers, yet biliary complications remain an important cause of death after liver transplantation, accounting for 15-34% of cases. Discussion of the etiology, early diagnosis, treatment, and effective prevention of this problem is directly related to the prognosis of liver transplantation and is necessary. There are many types of biliary complications after liver transplantation, and there is no uniform classification. Most of the literature classifies them into two major categories: biliary fistula and biliary obstruction. Biliary fistulae include anastomotic fistulae and biliary fistulae that occur after removal of the T-tube; biliary obstruction includes biliary strictures, biliary sludge formation, and biliary stones. In addition, other rare complications include dysfunction of the Oddi sphincter in the bile duct, mucous-like polyps in the bile duct, biliary torsion, bile duct hemorrhage, liver abscess, and stent-related complications. Although the occurrence of biliary complications is influenced by many factors, the biliary reconstruction technique is undoubtedly the most important risk factor. The two main biliary tract reconstruction techniques for living liver transplantation are bile-intestinal anastomosis and bile duct-bile duct end-to-end anastomosis. The bile-intestinal anastomosis was once the standard biliary reconstruction approach performed in the early days of living liver transplantation, but has been gradually replaced by the bile duct-bile duct end-anastomosis approach in recent years due to its alteration of the normal anatomy and potential for increased complications. The latter has the advantages of significantly shortening the operative time, avoiding contamination of the bile duct with intestinal contents, rapid recovery of postoperative gastrointestinal function, and facilitating endoscopic intervention to manage biliary complications, and has become the mainstream approach for biliary reconstruction. Fan et al [1] from the University of Hong Kong reported that the ICU treatment time, hospital days and in-hospital morbidity and mortality rate were lower in the bile duct-end anastomosis group than in the bile-intestinal anastomosis group.Hwang et al [2] analyzed 259 living liver transplants, of which more than 60% used bile duct-end anastomosis to reconstruct the biliary tract, with a mean follow-up time of 46 months, and found that the bile duct caliber.