Abstract: OBJECTIVE To observe and compare the impact of two anesthesia modes on postoperative pulmonary function and inflammatory indexes of the elderly patients undergoing abdominal surgery. METHODS A total of 100 patients who received abdominal surgery in the First Affiliated Hospital of Xiamen University from Aug 2017 to Sep 2018 were enrolled in the study and randomly divided into the experimental group with 50 cases and the control group with 50 cases.The control group was given general anesthesia, while the experimental group was given general anesthesia combined with epidural anesthesia.The lung function indexes such as maximum voluntary ventilation（MVV） per minute, resting ventilation per minute（VE）, forced expiratory volume in the first second（FEV1）, residual gas volume（RV） and total lung capacity and immune function indexes CD₃⁺, CD₄⁺ and CD₈⁺ as well as inflammatory indexes such as interleukin-6（IL-6）, interleukin-8（IL-8） and tumor necrosis factor-α（TNF-α） were compared between the two groups of patients before the surgery and after the surgery for 1 and 3 days; the surgery-related indexes including postoperative recovery time, extubation time, anesthesia time and time of recovery of autonomous respiration were observed and recorded, and the incidence of pulmonary infection was compared. RESULTS The postoperative recovery time, extubation time, anesthesia time and time of recovery of autonomous respiration of the experimental group were respectively（7.24±3.12）min,（11.35±7.34）min,（4.13±1.14）h and（7.34±1.54）min, significantly shorter than those of the control group（P＜0.05）.The ratios of MVV to FEV1 of the experimental group were respectively（89.25±7.80）% and（90.01±7.79）% after the surgery for 1 and 3 days, higher than those of the control group.The ratios of RV to TLC of the experimental group were（32.12±4.29）% and（31.23±4.30）%, significantly lower than those of the control group（P＜0.05）.The levels of CD₃⁺, CD₄⁺ and CD₈⁺ of the experimental group were significantly higher than those of the control group after the surgery for 1 day（P＜0.05）; the levels of IL-6, IL-8 and TNF-α of the experimental group were significantly lower than those of the control group（P＜0.05）.There were no significant differences in the immunologic indexes and inflammatory factors between the two groups of patients after the surgery for 3 days.The incidence of pulmonary infection of the experimental group was 6.00%（3/50）, significantly lower than 22.00%（11/50） of the control group（P＜0.05）. CONCLUSION The general anesthesia combined with epidural anesthesia may significantly reduce the incidence of postoperative pulmonary infection in the elderly patients undergoing abdominal surgery and improve the immune state as well as the lung function.