Medically induced biliary injury is a serious surgical complication in biliary surgery, often with more serious consequences for patients. Although the proportion of biliary tract injuries is not high, the absolute number of biliary tract injuries cannot be ignored because of the huge number of biliary tract surgeries, especially complex biliary tract injuries (bismuth type III, IV, V), and foreign reports have reported that this type of injury accounts for more than 80% of the entire biliary tract injuries. The incidence of its long-term complications is high, and some patients require reoperation or even multiple operations with poor surgical results, causing great pain to the patient. Clinical causes of biliary tract injury include unclear anatomical structures, anatomical variants, poor anesthesia, inflammation resulting in heavy adhesions to surrounding tissues, blind confidence of the surgeon, and unskilled technical operation. Medical biliary tract injury is characterized by relatively insidious injury, injury to the bile duct for the normal bile duct is very thin, if biliary tract injury is not detected in a timely manner or improperly handled, more long-term complications, often causing more serious consequences to patients or even catastrophic consequences. Therefore, biliary tract injury is the first thing to try to prevent, biliary tract injury after treatment of many methods, the general principle is to lift the obstruction, unobstructed drainage, to prevent repair and reconstruction of the bile duct restenosis, remedial measures mainly emphasize the early detection and correct treatment. Early detection of biliary tract injury is the first requirement for a one-stage anastomosis. Therefore, the anatomical structure of the biliary tract must be identified during surgery, and the surgical wound must be carefully examined for bile leakage and two duct openings in the resected cystic duct before closing the abdomen. Intraoperative cholangiography should be performed immediately when biliary tract injury is suspected, and expert consultation must be requested when identification is particularly difficult. In the early postoperative period, the inflammatory edema of the biliary tract and surrounding tissues is not obvious, the tissues are not brittle, the patient’s general condition is better, the systemic inflammatory reaction and liver and kidney function are not heavily impaired, the biliary tract is easily anastomosed and has strong healing ability, and the chances of biliary leakage and scar stenosis are much less. The author advocates that one-stage anastomosis is feasible within 24 h. If the local and systemic conditions are good, one-stage anastomosis is also feasible beyond 24 h. When symptoms such as jaundice or abdominal pain appear later after surgery, or when biliary injury is suspected, it is important to combine radiological and endoscopic methods to clarify the diagnosis as soon as possible. Most patients are referred from primary hospitals and often have a long injury time, requiring local drainage first and biliary reconstruction after systemic and local conditions have improved. Local ischemia plays an important role in biliary stricture after biliary reconstruction. Most biliary tract injuries are associated with injury to the intrinsic hepatic artery and right hepatic artery, chemical irritation of the biliary tract dissection by bile, and a long defective biliary tract can affect the blood supply to the reconstructed biliary tract, which becomes an important cause of biliary stenosis and recurrent cholangitis after reconstruction. This may explain the superiority of bile duct repair + T-tube support drainage over bile duct repair for the same type of injury. Complex biliary tract injuries often involve separation of the right and left hepatic ducts, requiring plastic surgery for anastomosis, and in a small number of patients, only right hepatic duct-jejunum Roux-en-Y anastomosis or right and left hepatic ducts with separate jejunal Roux-en-Y anastomosis can be performed. In this case, care must be taken not to damage the blood supply, and there are reports from abroad that bile duct reconstruction with simultaneous repair of the injured right hepatic artery or the intrinsic hepatic artery has achieved good results. Since the injured bile duct is a normal bile duct with a thin diameter, the suture should be made with absorbable thread, and the operation should be done gently and delicately, preferably by an experienced physician. And placing the internal support tube can make the bile duct fully drain into pressure, avoid postoperative anastomotic fistula or stenosis, facilitate postoperative dynamic observation, flushing and removal of residual stones, and preserve access for subsequent treatment. However, the diameter of the support tube should be appropriate so that there is no tension or collapse at the anastomosis, otherwise it may cause ischemia, necrosis, biliary fistula or stricture. The duration of the support tube can be determined according to the anatomical and pathological conditions of the extrahepatic biliary tract and the estimation of the maturation time of fibrosis, generally more than six months. Previously, it was thought that the longer the jejunal collaterals could be anti-reflux, but this is not the case. Excessively long output intestinal collaterals are prone to folding, twisting, adhesions and incomplete obstruction, which make the contents retained, bacterial multiplication, and more prone to retrograde biliary infection, the main cause of retrograde infection is anastomotic stenosis and poor drainage, and ischemia is an important factor leading to anastomotic stenosis. Biliary-intestinal Roux-en-Y anastomosis, because the anastomosis is close to the hepatic portal, is relatively rich in blood supply and rarely leads to anastomotic stenosis. It is generally believed that jejunal collaterals longer than 20 cm can prevent reflux, and 40 cm is generally beneficial. However, if bile duct repair + T-tube support drainage is performed in order to maintain the normal biliary physiological structure, higher long-term complications often occur due to local ischemia and difficult operation. In conclusion, medical bile duct injury is an everlasting issue in biliary surgery, which mainly lies in prevention. Once biliary injury occurs, early detection and proper management are needed to relieve obstruction, unobstructed drainage, and prevent long-term complications after repair and reconstruction. The results of this study showed that the bile-intestinal Roux-en-Y anastomosis for complex medically induced biliary tract injury has fewer long-term complications than biliary tract repair + T-tube supported drainage, and achieves more satisfactory results.