Diabetes mellitus is one of the most progressive disease in the world especially type 2. It is known that injection of streptozotocinin terms of previous injection of nicotinamidecauses the main metabolic violations of diabetes mellitus type 2 in rats. The aim of our study was to evaluate the effect of Poterium sanguisorba extract on body weight, blood glucose, plasma insulin and lipid profile in streptozotocin-nicotinamide induced diabetic rats. Our results showed that in streptozotocin-nicotinamide induced diabetic rats were observed weight loss, decreased insulin sensitivity, hyperinsulinemia, increased insulin resistance coefficient, increased lipid profile and atherogenic index. Poterium sanguisorba extract was able to improve insulin resistance, glucose toleration, rectifies dyslipidemia in streptozotocin-nicotinamide induced diabetic rats.