Diagnosis of cholangiocarcinoma (CCA) is difficult when patients do not show jaundice. The aim of thisstudy was to examine the feasibility of using the total serum bile acid (TSBA) level as an aid for the diagnosisof CCA in patients without jaundice. For this purpose, TSBA of the following groups were measured using aBeckman Synchron CX4 clinical chemistry analyzer: 60 cases of CCA with total serum bilirubin ≤2 mg/dL(low total bilirubin group, LTB); 32 cases of CCA with total serum bilirubin >2 mg/dL (high total bilirubingroup, HTB); and 115 healthy controls. Liver function parameters such as serum cholesterol, albumin, alanineaminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were also examined.The results showed that the TSBA of both LTB and HTB groups of the CCA patients were significantly higherthan that of the healthy controls. Also, significant correlation was observed between TSBA and total bilirubinlevels in the HTB group of CCA patients. However, no such correlation was seen in the LTB group. The cut-offvalue of TSBA was determined for the LTB group of CCA patients using the receiver operating characteristiccurve analysis, and it was 6.05 μmol/L with the sensitivity and specificity of 46.7% and 84.4%, respectively. Inaddition, the ALP level was correlated well with the TSBA level and ALP in HTB group was significantly higherthan that of LTB group. Moreover, the combination of high TSBA and high ALP levels gave higher specificityup to 97.4%. TSBA might be useful for the diagnosis of CCA patients without jaundice.