Abstract: Objective To investigate the effect of Wumei Decoction combined with metformin on glucose metabolism and homeostasis model assessment of insulin resistance(HOMA-IR)in patients with type 2 diabetes. Methods Totally 102 patients with type 2 diabetes were randomly divided into control group(n=51)and combination group(n=51). The control group was treated with metformin, and the combination group was treated with Wumei Decoction on the basis of the control group. Glucose metabolites factors, islet function indicators, scores of traditional Chinese medicine(TCM)syndrome and clinical efficacy before and after treatment were compared between the two groups. Results After treatment, the levels of fasting blood glucose(FBG), 2 h postprandial blood glucose(2 hPG)and glycosylated hemoglobin(HbA1c)decreased significantly in both groups, and these indexes in the combination group were significantly lower than those in the control group(P<0.05). After treatment, levels of HOMA-IR andfasting insulin(FINS)reduced significantly in both groups, while homeostasis model assessment of islet β cell(HOMA-β)level increased significantly in both groups. The levels of HOMA-IR and FINS in the combination group were significantly lower than those in the control group, while HOMA-β level was significantly higher than that in the control group(P<0.05). After treatment, the score of TCM syndrome in the combination group was significantly lower than that of the control group, while total effective rate was significantly higher than that of the control group(P<0.05). Conclusion Wumei Decoction combined with metformin is effective in the- treatment of patients with type 2 diabetes, which can effectively control blood glucose level, alleviate insulin resistance and promote the recovery of islet cell function.