Background: Diabetes mellitus (DM) is a complex metabolic disorder involving many organs and can devastate the lives of affected individuals. It is characterized by chronic high blood glucose that could lead to morbidity and mortality. The number of people suffering from diabetes worldwide is increasing at an alarming rate. It is predicted that about 366 million people are likely to be diabetic by the year 2030. Since all of the previous studies have focused on the therapeutic role of (Allium polyrhizum Turcz. ex Regel) preparations in diabetes mellitus, we investigated the preventive effect of oral administration of (Allium polyrhizum Turcz. ex Regel) extract on the changes of biochemical factors and histopathology alterations in hepatic tissue caused by diabetes. Therefore, this study aimed to investigate the effect of water extract (Allium polyrhizum Turcz. ex Regel) on the metabolism of rats with diabetes induced by a high-fat diet and streptozotocin. Aim: To investigate the antidiabetic properties of aqueous extract of (Allium polyrhizum Turcz. ex Regel) and its beneficial effect on hematological parameters in streptozotocin-induced diabetic rats. Materials and Methods: Experimental was performed at the Institute of Mongolian Medicine and Chemistry, Inner Mongolia University. Male Wistar rats weighing (180 g) were obtained from The Animal Experimental Unit of Mongolia Medicine and Chemistry Research Center, Inner Mongolia University. The rats were housed in well-aerated individual cages in an animal room and maintained in a temperature-controlled room (24±25°C) with a 12 h light/12 h dark cycle, 50-60 % humidity. They were fed with normal commercial chow and water ad libitum. Throughout the experiments, animals were processed according to the suggested international ethical guidelines for the care of laboratory animals, and all experimental procedures were approved by the Animal Care and Use Committee of Inner Mongolia University. After 4 weeks, the rats were fasted for 8 h before blood sampling, water was not restricted. Blood samples were collected from the orbital venous plexus. Results: The blood glucose level was significantly increased in model group 24.14±2.28 mmol/L, to Control group 5.31±0.49 mmol/L. Oral administration of Allium polyrhizum Turcz.ex Regel treated group 10.5±4.05 mmol/L, Metformin treated group 9.05±2.71 mmol/L resulted in significantly decreased blood glucose levels less model group. Conclusion The results of this study indicate that Allium polyrhizum Turcz.ex Regel possesses hypoglycemic, hypolipidemic, and antioxidant effects in STZ-induced diabetic rats and therapy of diabetes and its complications especially when used for a longer period.