Abstract： Objective： To observe the curative effect of modified Yiqi Fuzheng Jiedu Decoction on patients with postoperative chemotherapy for gastric cancer and its effect on tumor markers and gastrointestinal function. Methods： A total of 124 cases of patients with postoperative chemotherapy for gastric cancer were divided into the control group and the trial group according to the random number table method， with 62 cases in each group. The control group was treated with intravenous injection of Oxaliplatin and oral administration of Capecitabine Tablets，and the trial group was additionally treated with modified Yiqi Fuzheng Jiedu Decoction based on the treatment of the control group. The treatment courses in the two groups lasted for 1 month. Clinical effects and the time of recovery of bowel sounds， first exhaust， and defecation were compared between two groups. Traditional Chinese medicine (TCM) syndrome scores and the levels of tumor markers [serum cytokeratin 19 fragment 21- 1 (CYFRA21- 1)， carbohydrate antigen 199 (CA199)，tissue peptide specific antigen (TPS)，and human epididymal protein 4 (HE4)]，inflammatory factors [interleukin-6 (IL-6) and interleukin-10 (IL-10)]，and T lymphocytes [CD4+， CD8 + ， and CD4 +/CD8 + ] in peripheral blood were compared before and after treatment between the two groups. Results：The total effective rate was 83.87% in the trial group and 66.13% in the control group， the difference being significant (P＜0.05). After treatment， the time of recovery of bowel sounds， first exhaust， and defecation in the trial group was earlier than that in the control group (P＜0.05). After treatment， TCM syndrome scores of upper abdominal pain， abdominal distension， fatigue， and poor intake in the two groups were decreased when compared with those before treatment (P＜0.05)，and the above scores in the trial group were lower than those in the control group (P＜0.05). After treatment，the levels of CYFRA21- 1， CA199， TPS， and HE4 in serum in the two groups were decreased when compared with those before treatment (P＜0.05)， and the above indicators in the trial group were lower than those in the control group (P＜0.05). After treatment，the levels of IL-6，IL-10，and CD8+ in serum in the two groups were decreased when compared with those before treatment (P＜0.05)，and the levels of CD4+ and CD4+/CD8+ were increased when compared with those before treatment (P＜0.05)；the levels of IL- 6，IL- 10，and CD8 + in the trial group were lower than those in the control group (P＜0.05)，and the levels of CD4 + and CD4 +/CD8 + in the trial group were higher than those in the control group (P＜0.05). Conclusion：For patients with postoperative chemotherapy for gastric cancer，modified Yiqi Fuzheng Jiedu Decoction can enhance clinical effects，improve TCM syndromes and immune function，reduce the levels of tumor markers，and help promote the recovery of gastrointestinal function.