Objective To modify the method of establishing type 2 diabetic model in rats with streptozotocin ( STZ) and high- carbon hydrate-fat diet. Methods 40 male SD young rats were selected and the modified key points of methods were as following，1 ﹚ the rats for establishing type 2 diabetic model were 4 weeks old;2 ﹚ to determine the subclinical type 2 diabetes dose of STZ by experiments;3 ﹚ collecting blood from caudal vein，caudal artery and eyeball for the biochemistry test of rats. Results The blood glucose of rats significantly increased(13. 7 ± 1. 57 mmol /L) . The liver，pancreas，brain and kidney of model rats showed pathological changes. The survival time of model rats was longer( over 9months) . Conclusions The study improves the method of establishing type 2 diabetic model.