To investigate the effect of preoperative maltodextrin fructose solution on the diversity of gastric microflora and intestinal function. Method Select 100 gastric cancer patients requiring surgical treatment in our hospital from May 2021 to April 2022. They were divided into control group and experimental group by random number table method 50 cases in each group. The control group routinely fasted for 8 - 12 hours before surgery and fasted for 2 hours. The experimental group adopted the preoperative intervention of enhanced recovery after surgery ERAS concept maltodextrin fructose solution was administered 10 hours before surgery and maltodextrin fructose solution was administered 2 hours before surgical anesthesia . The general data blood glucoserelated indicators intestinal flora diversity intestinal function and complication rates were compared between the two groups. Result One week after operation the fasting insulin concentration and insulin resistance index of the experimental group were lower than those of the control group and the insulin sensitivity index was higher than that of the control group t = 9. 017 33. 522 3. 216 P<0. 01 < 0. 01 0. 002 One week after operation the Chao1 index and Shannon index of the experimental group were higher than those of the control group and the time to the first exhaust and the time to the first defecation were shorter than those in the control group t = 2. 720 6. 540 3. 344 3. 578 P= 0. 008 <0. 01 0. 001 0. 001 . There was no significant difference in surgical data operation time surgical bleeding surgical method etc. between the two groups P> 0. 05 . Conclusion Preoperative maltodextrin fructose solution can effectively improve postoperative blood glucose level and intestinal flora diversity thereby improving intestinal function without increasing the incidence of complications.