ObjectiveTo investigate the value of triglyceride-glucose index （TyG） and triglyceride-glucose-body mass index （TyG-BMI） in predicting new-onset diabetes mellitus （NODM） after distal pancreatectomy （DP）. MethodsA retrospective analysis was performed for the clinical data of 161 patients without diabetes before surgery who underwent DP in The First Affiliated Hospital of Xinjiang Medical University from January 2020 to December 2024， and according to the presence or absence of NODM after surgery， they were divided into NODM group and non-NODM group. Baseline clinical data were compared between groups. A multivariate logistic regression analysis was used to investigate the association of TyG and TyG-BMI with NODM， and the restricted cubic spline model was used to analyze the dose-response relationship between TyG/TyG-BMI and the risk of NODM. The receiver operating characteristic （ROC） curve was used to assess the performance of TyG and TyG-BMI in predicting NODM. ResultsAmong the 161 patients included in the analysis， 43 （26.7%） developed NODM after DP. Compared with the non-NODM group， the NODM group had significantly higher TyG （8.89±0.57 vs 8.54±0.56， P<0.001） and TyG-BMI ［232.18 （195.31 — 249.68） vs 195.39 （178.92 — 221.38）， P<0.001］. The multivariate logistic regression analysis showed that after adjustment for age， sex， and hemoglobin A1c， both TyG （odds ratio ［OR］=2.78， 95% confidence interval ［CI］： 1.43 — 5.39， P=0.003） and TyG-BMI （OR=1.02， 95%CI： 1.01 — 1.04， P<0.001） remained independent risk factors for NODM after DP. The restricted cubic spline analysis showed an approximately linear positive correlation between TyG/TyG-BMI and the risk of NODM. The ROC curve analysis showed that TyG and TyG-BMI had a moderate predictive value for NODM after DP， with an area under the ROC curve of 0.725 （95%CI： 0.683 — 0.867） and 0.719 （95%CI： 0.610 — 0.810）， respectively. ConclusionTyG and TyG-BMI are independent predictive factors for the onset of NODM after DP， with a certain predictive value in the diagnosis of NODM. These two simple metabolic indicators may become helpful tools for the early identification of patients at a high risk of NODM after DP.