Although the platelet distribution width (PDW) has been reported as a reliable predictor of prognosis in several types of cancer, to our knowledge the prognostic value of PDW in hilar cholangiocarcinoma (HC) has not been studied. The aim of the study was to investigate the prognostic value of PDW in HC patients. A retrospective analysis of 292 consecutively recruited HC patients undergoing radical resection with at least a 5-year follow-up. The optimal cutoff value of PDW was determined by receiver operating characteristic (ROC) curve. Survival analysis by the Kaplan-Meier method and the difference between the clinico-pathologic variables and survival was evaluated by log-rank analysis. Multivariate analysis identified independent prognostic risk factors of overall survival (OS). ROC curve analysis suggested that the optimal cutoff value for the PDW was 16.55. There were significant associations of high PDW with high white blood cell (P < .001) and high neutril-to-lymph ratio (P < .001). In a multivariate analysis, the PDW was an independent prognostic factor for overall survival (HR = 2.521, 95% CI 1.832-3.470, P < .001). In conclusions, our findings indicate that PDW may have clinical significance in predicting OS after surgery in HC patients.