Objective To investigate the effect of dapagliflozin combined with metformin in the treatment of type 2 dia-betes mellitus.Methods A total of 120 patients with type 2 diabetes mellitus admitted to Jiangle County General Hospi-tal of Sanming in Fujian Province from January 2022 to December 2023 were selected as the research objects and di-vided into control group(60 cases,treated with metformin alone)and observation group(60 cases,treated with dapa-gliflozin combined with metformin)according to different treatment methods.The blood glucose indexes(fasting plasma glucose,2-hour postprandial plasma glucose,glycated hemoglobin A1c),insulin indexes(homeostatic model assess-ment of insulin resistance,homeostatic model assessment of islet β-cell function),body mass index and total effective rate of treatment were compared between the two groups after treatment.Results The blood glucose index,insulin index and body mass index of the observation group were better than those of the control group,and the differences were sta-tistically significant(all P<0.05).The total effective rate of treatment in the observation group was higher than that in the control group,and the difference was statistically significant(P<0.05).Conclusion The combination of dapa-gliflozin and metformin has shown excellent efficacy in patients with type 2 diabetes mellitus.Which not only effec-tively control the patient's blood glucose level,but also significantly improve the insulin index and body mass index.