Abstract: Objective To investigate the proportion of malnutrition in patients with hilar cholangiocarcinoma(HC),and analyze the factors associated with the malnutrition and the influence of malnutrition to postoperative complications. Methods Total 53 cases of hilar cholangiocarcinoma met the criterion of radical excision in our hospital between January,2000 and January,2015 were enrolled into this study and the clinic date were reviewed. All of them were assigned into well nutrition group and malnutrition group according to the scored patient-generated subjective global assessment(PG-SGA).The relationship between the malnutrition and postoperative complications were evaluated. Results According to PGSGA,29 cases(54. 7%) were with malnutrition. The factors associated with malnutrition includedage,duration of jaundice,liver function classification by¹³C-methacetin breath test and stage of tumor(P < 0. 05 respectively),but not with gender,Bismuth- Corletttyping,BMI,preoperative albumin level and Child Pugh Score(P > 0. 05). The incidence of postoperativecomplications was higher in malnutrition group that did not receiving nutrition innervation than that in well nutrition group(χ²=4. 201,P=0. 040). There were no obvious differences in the incidence of postoperative complications between the malnutrition group that receive nutritional support and the well nutrition group(χ²=0. 438,P=0. 508). Conclusion The incidence of malnutrition is commonin patients with hilar cholangiocarcinoma before the surgery treatment,and perioperative nutritional support may reduce postoperative complications.