Abstract: Objective: To observe the clinical effect of modified Qingre Qushi Prescription assisting Lansoprazole for chronic atrophic gastritis and its effect on oxidative stress indexes. Methods: A total of 98 cases of patients with chronic atrophic gastritis were divided into the control group and the observation group according to the random number table method,with 49 cases in each group. The control group was treated with the oral administration of Lansoprazole Tablets, and the observation group was additionally treated with modified Qingre Qushi Prescription based on the treatment of the control group. Traditional Chinese medicine (TCM) syndrome scores, oxidative stress indexes including superoxide dismutase (SOD), glutathione peroxidase (GSH- Px) and malondialdehyde (MDA), inflammatory factors including tumor necrosis factor- α (TNF- α), C- reactive protein (CRP) and interleukin- 6 (IL- 6) before and after treatment were compared between the two groups. The clinical effects and the incidence of adverse reactions in the two groups were evaluated. Results:The total effective rate of treatment was 93.88% in the observation group, higher than that of 83.67% in the control group (P<0.05). After treatment, the levels of MDA,TNF- α,CRP,IL- 6,and pepsinogen (PG) Ⅱand the TCM syndrome scores in the two groups were decreased when compared with those before treatment (P<0.05), and the levels of SOD, GSH-Px, PGⅠ and gastrin-17 (G-17) were increased (P<0.05); the levels of MDA, TNF- α, CRP, IL- 6, and PG Ⅱand the TCM syndrome scores in the observation group were lower than those in the control group (P<0.05),and the SOD,GSH- Px,PGⅠ and G- 17 levels in the observation group were higher than those in the control group (P<0.05). The incidence of adverse events was 14.29% in the control group,higher than that of 4.08% in the observation group (P<0.05). Conclusion:Modified Qingre Qushi Prescription assisting Lansoprazole for chronic atrophic gastritis has a definite curative effect, and can alleviate oxidative stress damage and reduce the levels of inflammatory factors in patients with high safety.