Recently, the Department of Gastroenterology successfully performed ultra-fine gastroscopic transoral bile duct laser lithotripsy on an 86-year-old patient with difficult-to-take stones in the common bile duct. The patient, Grandma Li, was diagnosed with acute cholangitis, bile duct stones and gallbladder stones more than 30 years ago due to severe abdominal pain with high fever, and improved with conservative treatment, and has been treated conservatively in a local hospital 1-2 times a year since then. More than a year ago, he had another attack of acute cholangitis and went to our gastroenterology department, where ERCP was performed to remove a large number of stones from the bile ducts. After that, the patient still had intermittent episodes of cholangitis, and was hospitalized again on December 20, when ERCP showed a significant widening of the common bile duct by 2.5 cm. After full communication with the patient and family, Dr. Huang Yonghui performed an innovative ultra-fine gastroscopic transoral biliary laser lithotripsy on this patient on December 25, which crushed the stones into sediment and removed all of them, with a lithotripsy time of 5 minutes and a total operation time of 40 minutes. After the operation, the patient had no complications such as bile duct bleeding, biliary fistula and bile duct stricture, and no residual stones were found in the nasal cholangiogram, and he was discharged in a stable condition. The ultra-fine gastroscopic transoral bile duct exploration was first performed with ERCP, bile duct intubation was completed, papillary sphincterplasty was performed by applying CRE dilating balloon, and then the ultra-fine gastroscope (5.9 mm in diameter) was replaced to enter the common bile duct, allowing direct visual observation of lesions in the lumen of the bile duct for targeted biopsy or for treatment. The Department of Gastroenterology has completed one case of intrahepatic bile duct adenoma biopsy and one case of bile duct exploration after removal of a metal-clad stent placed for bile duct injury. Ultra-fine gastroscopic transoral bile duct laser lithotripsy starts with placing a laser fiber into the common bile duct through a nasogastroscope, the end of which comes into contact with the surface of the stone, and then emits laser light, which vaporizes the water on the surface of the stone to form a vacuole, which transmits energy to the stone and causes it to break up without damaging the surrounding tissues. Currently, the Department of Gastroenterology has completed 2 cases of ultra-fine gastroscopic endobiliary laser lithotripsy. This new technology is less traumatic than laparoscopic or open surgery for stone extraction, with fewer postoperative complications and faster postoperative recovery, and is a safe and effective endoscopic treatment for difficult-to-take bile duct stones.