Objective Toidentify factors contributing to posthepatectomy liver dysfunction (PHLD),focusing on the Functional remnant liver volume to spleen volume ratio (FreLSVR).Methods The clinical data of 74 patients undergoing precise liver resection from January 2016 to October 2017 were retrospectively analyzed.IQQA liver system was used to reconstruct the liver and spleen 3D image by using patients' preoperative abdominal CT image data.Tumor volume,3D estimated functional residual liver volume,spleen volume and FreLSVR were measured and calculated.Preoperative and postoperative liver function test,blood coagulation function test,operation time,intraoperative blood loss,and the volume of daily postoperative abdominal drainage were recorded.Correlations between multiple parameters and PHLD were analyzed.Results PHLD occurred in 16 (21.6％).Single factor analysis revealed that the standardized residual liver volume ratio (P＜0.05),FreLSVR (P＜0.05) and preoperative AST value (P＜0.05) were correlated with postoperative hepatic insufficiency.Multivariate regression analysis showed that FreLSVR (OR=0.535,95％CI=0.305～0.936,P＜0.05) was the only independent factor of PHLD.In the ROC curve analysis for FreLSVR,a cut-off value of 2.56 (AUC=0.824,Sensitivity 81.1％,specificity 71.7％.) was the appropriate value for predicting the risk of PHLD according to Youden index.Then the patients were regrouped according to this cut-off value.Compared with the FreLSVR＞2.56 group (53 cases),the highest postoperative INR value (1.46± 0.19 to 1.29± 0.29,t=-2.405,P＜0.05) was higher that of FreLSVR≤2.56 group,and the amount of average daily abdominal drainage in one and two weeks after operation was higher,(188.0(79.2 ～ 375.1)ml to 96.0(46.5 ～ 179.3)ml,P＜0.05) and (207.2(125.6 ～ 827.1)ml to71.8(14.0 ～ 179.8) ml,P＜0.05),respectively.Conclusion FreLSVR has significant correlation with postoperative hepatic dysfunction,and provides guidance for the safety of liver resection in the future.