According to WHO, India may have 80 million diabetic patients by the year 2030. Oxidative stress may occur as a result of increased free radical generation and/or decreased anti-oxidant defense mechanisms. In the course of evolution, organisms have developed some more or less refined mechanisms protecting them against the harmful activity of free radicals, both in enzymatic and non-enzymatic ways. Diabetes mellitus is one of the stress related disorder, its a state of increased free radical formation occurs. During diabetes homeostasis of carbohydrate, protein and lipid metabolism are improperly regulated by insulin. Streptozotocin (STZ), cytotoxic agent of pancreatic ?-cells induces diabetes by rapid depletion of ?-cells resulting in reduction insulin secretion. In traditional system of Indian medicine, plant formulation and combined extracts of plants are used as drug of choice rather than individual. Glymin, a polyherbal formulation developed by Kerala Ayurveda Ltd, was taken to evaluate the anti-diabetic, free radical scavenging, antioxidant and lipid lowering properties in STZ-induced diabetes.