Objective. To explore the best treatment of obesity in middle and old age. Methods. 80 obese patients in our hospital from January 2020 to December 2021 were randomly divided into the control group and the intervention group according to the numerical table method. The control group was treated with lifestyle intervention, while the intervention group was treated with dapagliflozin combined with lifestyle intervention. The effects of body weight, body mass index (BMI), waist circumference, and blood lipids (LDL, HDL, TC, and TG) were measured and compared. Anxiety and depression scores were assessed using the 2018 Revised Anxiety and Depression Scale. Results. There were no significant differences in body weight, BMI, and waist circumference between the control group and the intervention group before treatment. After treatment, the weight, BMI, and waist circumference of the intervention group were lower than those of the control group, and the difference was statistically significant ( P < 0.05 ). After treatment, LDL, TC, and TG in the two groups were decreased, and HDL was significantly increased ( P < 0.05 ). After treatment, the blood lipid level in the intervention group was significantly lower than that in the control group ( P < 0.05 ). Anxiety and depression symptoms improved in both groups, and there were no serious adverse effects. Conclusion. Dapagliflozin in combination with a lifestyle intervention effectively and safely treats excess weight in middle-aged and older adults, reverses obesity-related markers, and improves psychological symptoms. Its curative effect is better than that of using lifestyle intervention alone.