Objective:To observe the effect of gastric banding on STZ -induced type 2 diabetes rats model,and to primarily clarify its mechanism. Methods:42 type 2 diabetes rats were randomly allocated into operation group (group O) with 12 rats;sham group (group S) with 10 rats;diet control group(group F) with 10 rats and control group(group C) with 10 rats. Fasting glucose,fasting plasma leptin,fasting plasma insulin levels,fasting weight and food intake were measured before and after operation 1st,2nd,3 rd,4th,8th and 16 th week. Results:16 weeks after operation in the Group O,fasting glucose fell to(12.6±3.7)mmol/L,fasting plasma insulin increased to(42.7±9.2)mIU/L,fasting plasma leptin decreased to(14.6±3.3)pg/ml and weight declined to(212.6±15.1)g,had statistical significance compared with the levels of preoperation(P < 0.01). In the Group O,fasting plasma insulin was negatively correlated with fasting plasma glucose(r =-0.881,P < 0.01),and positively correlated with fasting plasma leptin(r = 0.784,P < 0.01).There was no significant difference between the Group F and O on fasting plasma insulin and leptin,excepte for the 3rd and the 4th week postoperation(P < 0.05). Weight had statistical difference after three weeks of operation in the Group O compared with that of Group F(P < 0.05). There was no difference on blood glucose between Group F and O after operation(P > 0.05). Conclusion:Gastric banding can reduce fasting glucose in STZ-induced type 2 diabetes rats. Diet control and Weight loss may be the major mechanism of blood glucose change in STZ-induced type 2 diabetes rats after Gastric banding operation.