BACKGROUND Laparotomy patients are occasionally diagnosed as having incidental periampullary cancers, making emergency pancreaticoduodenectomy (PD) inevitable. In this situation is difficult to decide whether to perform an emergency PD or a two-stage PD. MATERIAL AND METHODS A total of 27 patients who underwent emergency abdominal laparotomy were diagnosed with periampullary or pancreatic cancer during the operation without enough preoperative preparation. Ten patients underwent emergency one-stage PD and 17 patients underwent two-stage PD. Data of 137 patients with elective PD were selected as the control group. The preoperative, operative, and postoperative parameters, including hospital stay, medical cost, blood loss, and postoperative complications between elective PD and emergency PD (one-stage and two-stage) and between one-stage PD and two-stage PD were analyzed by chi-square test, Fisher test, or t test. RESULTS Patients undergoing emergency two-stage PD had less blood loss (P=0.014), while patients with one-stage PD had shorter hospital stay (P=0.004), shorter operation time (P=0.047), and lower treatment costs (P=0.003). Additionally, the complications rates between one-stage and two-stage PD had no significant difference (P=0.365). Elective PD was the optimal method due to shorter hospital stay (P<0.001), less hemorrhage (P<0.001), shorter operative time (P<0.001), and lower cost (P<0.001) compared with emergency PD. CONCLUSIONS Based on our experience, one-stage PD had advantages of shorter hospital stay, shorter operation time, and lower treatment costs, while two-stage PD had less blood loss. The emergency two-stage PD may be more suitable for patients with unstable vital signs if emergency PD is inevitable in an emergency laparotomy.