Objective: To investigate the effects of oat barley powder on glucose and lipid metabolism and oxidative stress in type II diabetic mice. Methods: ICR mice were fed high-fat diet， combined with small dose (50 mg/kg) intraperitoneal injection of streptozotocin to establish a diabetic mouse model. The adult mice were randomly divided into a high-fat group， a positive control group (metformin 200 mg/kg·d) and a high-fat oat barley powder group. Observe the changes in body weight and blood glucose of each group during the sample administration， take the blood from the eyeball after 6 weeks of sample administration， and detect blood lipids， fasting blood sugar and serum insulin. The liver tissue was collected to determine the activity of malonaldehyde (MDA)， superoxide dismutase (SOD)， glutathione peroxidase (GSH-Px) activity， and glutathione(GSH). Results: Compared with the high-fat group， the high-fat oat barley powder group can effectively alleviate the symptoms of diabetic mice. HE staining showed that oat barley powder improved the pathological state of the mouse pancreas； it could significantly reduce the fasting blood glucose level of type II diabetic mice (P<0.05)， it has a very significant effect on reducing HDL-c and LDL-c content (P<0.01)， there is no significant difference in TG content (P>0.05)， and it has a significant effect on TC reduction (P<0.05)； The level of GSH-px was significantly increased (P<0.05)， the level of SOD was significantly increased (P<0.05)， and there was no significant difference in the content of MDA(P>0.05). Compared with the high-fat group， the high-fat oat barley powder group had a very significant increase in serum insulin (P<0.01)， and the high-fat group had a very significant increase (P<0.01) compared with the blank control group. The content of lactic acid bacteria in the intestinal flora in the high-fat group fed oat barley meal was improved compared with the high-fat group. Conclusion: Oat barley powder has the effect of lowering blood sugar in type II diabetic mice， and has a certain regulatory effect on the disorder of blood lipid metabolism. The specific mechanism of lowering blood sugar and lipid may be related to improving the body's antioxidant activity.