Diabetes is metabolic disorders which results from pancreatic beta cells dysfunction & insulin resistance and are characterized by hyperglycemia. The in-vivo anti-diabetic potential of P. amarus was also determined so as to justify the traditional usage of the plant in treating diabetes. The result of the present study confirmed that the methanolic extract of P. amarus possess significant anti-diabetic activity in-vivo, this shows that the plants has the potential for the development of drugs in combating diabetes.