Diabetes mellitus is a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. Type 1 diabetes, or juvenile-onset diabetes, results from a cellular-mediated autoimmune destruction of the β-cells of the pancreas. Type 2 diabetes, or adult-onset diabetes, is a term used for individuals who have insulin resistance, a condition that makes it harder for the cells to properly use insulin, and usually have relative insulin deficiency. The diabetes causes the onset of chronic complications and diabetic neuropathy is one of the most debilitating complications. In this study, the hypoglycemic effect and the preventive effect of diabetic complications of Dioscorea rhizoma extract(DRE) were examined in rodent model. We investigated the glucose tolerance test and long term hypoglycemic effect of DRE in Type 1 streptozotocin-induced diabetic rats and Type 2 diabetic db/db mice. DRE showed a hypoglycemic effect on blood glucose levels than that of control group in Type 1 streptozotocin-induced diabetic rats and Type 2 diabetic db/db mice. On the basis of our results, we conclude that long-term use of DRE might help decrease blood glucose level and prevention of diabetes-associated complication.