The incidence of diabetes mellitus is on the rise and it is associated with disturbance of carbohydrate, fat and protein metabolism. Many herbal preparations and plant extracts are used with varying degree of success in the management of type 2 diabetes. Jamboola is one such polyherbal formulation composed of 5 medicinal plants which is used as an ayurvedic formulation in Andhra Pradesh, India to treat diabetes and claims no scientific evidence for its effectiveness as a polyherbal formulation. The herbal constituents of jamboola are known to possess anti-diabetic, antioxidant properties, and are used in indigenous system of medicine for the treatment of diabetes mellitus. According to the traditional system of Indian medicine, a combination of substances is used to enhance the desired activity and to eliminate unwanted side effects. In view of the above considerations the present study has been under taken to evaluate the hypoglycaemic, anti-hyperglycaemic activity of jamboola and to add a scientific proof to its efficacy. Glibenclamide at a dose of 0.45 mg/kg exhibited significant hypoglycaemic and antihyperglycaemic activity. Jamboola exhibited significant hypoglycaemic and anti-hyperglycaemic activity at 3 ml/kg than 1.5 ml/kg.