In the present study, an attempt was made to evaluate the effects of hydro-alcoholic extract of Aloe vera in streptozotocin-induced diabetic mice. A total 48 white lab mice were divided into four groups (n=12). One group served as control which was neither diabetic nor treated with Aloe vera. Second group was normal and treated with Aloe vera orally at the dose rate of 300 mg/kg. Third group was diabetic and in fourth group was also diabetic but treated with Aloe vera. The glucose analogue, streptozotocin was used to induce diabetes. After a week treatment of Aloe vera, the glucose level returned to normal. Histologically, the islet of Langerhens in pancreas was damaged in diabetic mice which were restored by feeding Aloe vera. The hepatocytes of diabetic rats were swollen. These degenerative changes were repaired by supplementation of Aloe vera. Similarly, in the kidney and small intestines, the degenerative changes were restored by the addition of Aloe vera in the feed. The present study demonstrated that Aloe vera have a beneficial effects in treatment of diabetes.