The web of the common bile duct is an extremely rare anomaly and the cause of the obstructive jaundice. We experienced a case of the congenital web of common bile duct in a 42 years old male who complained of jaundice for 10 days prior to admission without choledocholithiasis and cholangitis. An endoscopic retrograde cholangiopancreatography revealed a common bile duct web (transverse, diaphragmatic type) and the diagnosis was confirmed by an endoscopic forcep biopsy. We reported a case of the congenita1 web of the common bile duct which was treated with a stent insertion and balloon dilatation. (Korean J Gastrointest Endosc l8: 426-431, 1998)