A rare case of idiopathic benign biliary stricture is reported. A 50-year-old man with liver dysfunction underwent ultrasonography, which revealed dilation of the intrahepatic bile ducts, and endoscopic retrograde cholangiopancreatography, which revealed a short, ring-like stenosis at the junction of the left and right hepatic ducts. Although a benign stricture was suspected, radiologic tests alone were insufficient to make a firm diagnosis. Therefore, a cholecystectomy and resection of the extrahepatic biliary tract were performed. Microscopic examination of the resected specimen demonstrated no evidence of malignancy. The final diagnosis was mild, localized, chronic cholangitis. The patient had not had previous biliary tract surgery, choledocholithiasis, nor did he have a congenital abnormality of the biliary tract, bile duct carcinoma, or pancreatic disease. Since there was no evidence of primary sclerosing cholangitis, the stricture was considered to be idiopathic.