A 74-year-old woman was admitted to our hospital with a 2-week history of jaundice. Percutaneous transhepatic cholangioscopy revealed a nodular tumor originating in the upper part of the common hepatic duct, which was invading the confluence of the right and left hepatic ducts. Microscopic examination of biopsy specimens revealed adenocarcinoma. Abdominal ultrasonography and computed tomography demonstrated multiple enlarged lymph nodes around the extrahepatic bile duct and the common hepatic artery. Laparotomy revealed lymph node enlargement in the hepatoduodenal ligament, behind the pancreatic head, and along the common hepatic and left gastric arteries. Extended left hepatic lobectomy, caudate lobectomy, and resection of extrahepatic bile duct with extended lymph node dissection were performed. The histology of permanent specimen revealed no tumor metastasis but a sarcoid reaction in the lymph nodes. The patient is in good health 21 months after the operation, without any evidence of recurrence. This is the first successfully resected case of hilar cholangiocarcinoma associated with sarcoid reaction in the regional lymph nodes.