OBJECTIVE：To observe the efficacy and safety of metformin combined with rosiglitazone in the treatment of incipient type 2 diabetes. METHODS：160 patients with incipient type 2 diabetes were randomly divided into observation group and control group. Based on the diet control and exercise therapy， control group was orally given 0.5 g Metformin hydrochloride tablet， 3 times a day； observation group was additionally given 4 mg Rosiglitazone maleate tablet， once a day. They were treated for 24 weeks. Clinical efficacy， body mass index （BMI），fasting plasma glucose （FPG）， total cholesterol （TC）， triglyceride （TG），2 h postprandial glucose（2 h PG），glycated hemoglobin （HbA1c），fasting plasma insulin（FINS） level，insulin resistance index （HOMA- IR） and insulin sensitivity index （HOMA-IAI） before and after treatment， and incidence of adverse reactions in 2 groups were observed. RESULTS：The total effective rate in observation group was significantly higher than control group， the difference was statistically significant（P＜0.05）. Before treatment， there were no significant differences in the above-mentioned indexes（P＞0.05）. After treatment， BMI、FPG、TC、TG、2 h PG、HbA1c、FINS、HOMA-IR in 2 groups were significantly lower than before， FPG， 2 h PG， FINS， BMI and HOMA-IR in observation group was lower than control group， HOMA-IAI was significantly higher than before， and observation group was higher than control group， the differences were statistically significant （P＜0.05）. There was no significant difference in the incidence of adverse reactions between 2 groups（P＞0.05）. CONCLUSIONS：The efficacy and improvement of glucose metabolism， insulin resistance and insulin sensitivity of rosiglitazone combined with metformin are superior to metformin alone in the treatment of incipient type 2 diabetes， with similar safety.