To investigate the influencing factors of post-pancreatectomy acute pancreatitis (PPAP) after pancreaticoduodenectomy (PD). Methods    The clinical data of 205 patients who had undergone PD at the Department of Pancreatic and Metabolic Surgery, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, were collected consecutively from March 2022 to August 2023 using retrospective case-control study method. The patients were divided into the PPAP group (45 cases) and the non-PPAP group (160 cases) according to the occurrence of PPAP after PD. The differences of preoperative baseline characteristics, intraoperative and postoperative characteristics, and the rates of postoperative complications between the two groups were compared and logistic regression model with stepwise forward method was utilized to identify the influencing factors of PPAP after PD. Results  The incidence of PPAP after PD in this study was 22.0%. The results of univariate analysis showed that age, the proportion of male, ratio of hard pancreas, the diameter of the main pancreatic duct and the rate of pancreatic ductal adenocarcinoma in the PPAP group were lower than those in the non-PPAP group, and the BMI, operation duration and FRS score in the PPAP group were higher than those in the non-PPAP group, with statistical significance (P<0.05). The results of multivariate analysis showed that older age (OR=0.957, 95%CI 0.927-0.987, P=0.006) was an independent protective factor for PPAP in PD patients, and soft pancreatic texture (OR=7.725, 95%CI 2.104-28.359, P=0.002) and long surgery time (OR=1.006, 95%CI 1.002-1.010, P=0.006) were independent risk factors for PPAP after PD. The incidence of clinically relevant postoperative pancreatic fistula, abdominal infection and the duration of postoperative hospitalization were significantly higher in the PPAP group than those in the non-PPAP group, with statistical significance (P<0.05).  Conclusion    Young age, soft pancreatic texture and long surgery time were independent risk factors for the occurrence of PPAP after PD.