Clinical evidence on the role and timing of ERCP in acute biliary pancreatitis has been controversial, and many studies have been devoted to this issue, such as the effectiveness of early ERCP with and without EST, and the effectiveness of conservative treatment alone versus conservative treatment combined with ERCP. Six meta-analyses and systematic reviews have been conducted to summarize these clinical studies, and the inclusion of these articles differs depending on the method of evaluation and the criteria developed. However, the common conclusion is that in the presence of cholangitis or biliary obstruction, early ERCP (within 24-72 hours of admission) reduces mortality or local and systemic complications, and vice versa. Indications for ERCP: 1. Patients with acute onset within 24 to 48 hours with signs or symptoms of cholangitis (e.g., fever, jaundice, sepsis, etc.) or persistent biliary obstruction (conjugated bilirubin >5 mg/dL [86 μmol/L]); 2. Patients with worsening disease (increased pain, decreased white blood cells, altered vital signs) or enzymatic changes in liver disease; 3. ) suggesting the presence of common bile duct stones. Absolute contraindications: 1. Vital signs are unstable, which prevents sedation or general anesthesia; 2. The patient does not agree to ERCP; 3. The endoscope operator is inexperienced. Relative contraindications: 1. Gastroduodenal lesions or anatomical changes caused by surgery that prevent the endoscope from reaching the large duodenal papilla; 2. The presence of severe coagulation dysfunction.