ObjectiveTo investigate the occurrence of postoperative healthcareassociated infection(HAI) in patients with hepatobiliary malignant tumor, explore the related risk factors, so as to provide the basis for taking effective prevention and control measures.MethodsThe occurrence of postoperative HAI in patients with hepatobiliary malignant tumor in a hospital from January 2012 to December 2014 were retrospectively analyzed, risk factors for postoperative HAI were analyzed through reviewing and collecting patients’ medical data. ResultsA total of 302 patients were investigated, 42 (13.91%) developed postoperative HAI, no multiple site infection occurred, the main infection site was deep surgical site (n=10, 23.81%）, followed by lower respiratory tract (n=9, 21.43%）and digestive system (n=7, 16.67%). Of 42 infection cases, 38(90.48%）were sent specimens for pathogenic culture, 36 pathogenic strains were isolated, 31 (86.11%) of which were gramnegative bacteria,  and 5 (13.89%) were grampositive bacteria. Multivariate logistic analysis showed that operation duration≥2 hours (OR=1.48), overweight (or obesity)(OR=1.40), and preoperative radiotherapy (OR=2.98) were independent risk factors for postoperative HAI in patients with hepatobiliary malignant tumor (all P<0.05).ConclusionIncidence of postoperative HAI is high in patients with hepatobiliary malignant tumor, risk factors are long length of operation, overweight (or obesity), and preoperative radiotherapy, effective prevention and control measures against risk factors should be taken.