Cholangiocarcinoma, a malignancy of the biliary duct system, tends to grow slowly and to infiltrate the walls of the ducts, dissecting along tissue planes and leading to biliary tract obstruction. In a retrospective case review, 62 cases diagnosed with cholangiocarcinoma between January 1997 and December 2001 at the King Chulalongkorn Memorial Hospital in Bangkok were studied. The most commonly observed clinical symptoms and signs were fever (96.8%), abdominal pain (87.1%) and malaise or weakness (83.9%). Fifty-one of the 62 tumours detected were distal extrahepatic (82.3%), seven perihilar (11.3%) and four intrahepatic (6.7%). There was a significant increase in serum bilirubin and marked elevation of serum alkaline phosphatase. Almost half (45.2%) of the patients presented with other pathological conditions, mostly cholangitis (19 cases) resulting from acute biliary tract obstruction and ascites (13 cases). The pathogens detected were similar in cases of cholangitis alone and cholangiocarcinoma. The major risk factor for this cancer in Thailand is believed to be exposure to liver fluke in insufficiently cooked traditional foods. As it is still endemic in Thailand, continuous prevention and surveillance of this public health problem are necessary.