Abstract： Objective： To observe the clinical effect of Yiqi Yangyin Huoxue tang combined with dimethylbiguanide for patients with type 2 diabetes mellitus. Methods：A total of 96 cases of patients with type 2 diabetes were randomly divided into the control group and the treatment group， 48 cases in each group. The control group was treated with dimethylbiguanide，and the treatment group was additionally treated with Yiqi Yangyin Huoxue tang based on the treatment of the control group. Both groups were treated for three courses， with four weeks being a course. After treatment， the clinical effect and the levels of blood glucose and blood lipid including total cholesterol(TC) and triglyceride(TG) in the two groups were compared and analyzed. Results：The total effective rate was 95.83% in the treatment group，and 83.33% in the control group， the difference being significant(P＜00.05). Before treatment， there was no significant difference being found in the comparison of the levels of fasting blood glucose，two- hour postprandial blood glucose，TC and TG between the two groups(P＞0.05). After treatment，the levels of fasting blood glucose，two-hour postprandial blood glucose，TC and TG in the two groups were decreased when compared with those before treatment(P＜0.05)，and the levels of fasting blood glucose and blood lipid in the treatment group were lower than those in the control group(P＜0.05). Conclusion：The therapy of Yiqi Yangyin Huoxue tang combined with dimethylbiguanide has definite effect in treating type 2 diabetes mellitus，which can effectively reduce the levels of blood glucose and blood lipid in patients.