Objective To investigate the effects of different ventilation modes on postoperative pulmonary complications in elderly patients undergoing abdominal surgery. Methods The patients who underwent upper abdominal surgery under general anesthesia in Chengdu Office Hospital of the People’s Government of Tibet Autonomous Region between February 2020 and February 2021 were selected. Patients were randomly divided into volume controlled ventilation (VCV) group, pressure controlled ventilation (PCV) group, and pressure controlled ventilation-volume guarantee (PCV-VG) group according to the random number table method. All the three groups adopted the internationally recognized lung protective ventilation strategy. The transcutaneous arterial oxygen saturation and respiratory mechanics indicators of three different time periods, as well as pulmonary symptoms and signs and laboratory imaging examinations 7 days after surgery were recorded. The incidence of postoperative pulmonary complications in the three groups of patients were evaluated using the Melbourne Group Scale Version 2. Results A total of 120 patients were included, with 40 in each group. There was no statistically significant difference in the general situation of the three groups of patients (P>0.05). The platform pressure and compliance of three different time periods all changed over time (P<0.05). There were statistically significant differences in the occurrence of pulmonary complications and hospital stay among the three groups 7 days after surgery (P<0.05). Conclusion Under the internationally recognized lung protective ventilation strategy, PCV-VG mode can significantly reduce the incidence of pulmonary complications 7 days after abdominal surgery, shorten the length of hospital stay, and improve the quality of life in elderly patients.