Objective: To observe the effects of Xingyi Jiangtangling on the of serum nitric oxide (NO)and plasma endothelin vessels (ET) in diabetic rats. Method: The model of diabetic rats was established by one-off high-dose intraperitoneal injection of streptozotocin and then concomitant hypodermic injection with thyroid.Then the changes of theNo1-ET will be obtaind through observation and comparison between drug treatment group and the control model.Xingyi jiangtangling and liuweidihuangwan in the treatment group can not only decline the rat blood sugar but improve the changes of the No

ET-1. Result: that of the effects of the Xingyi Jiangtangling are better than the positive control group of Liuweidihuangwan obviously. It was statistically significant ( P < 0.05). Conclusion: Xingyi jianggtangling plays an important role in the process of improving blood flowing and reducing diabetic complications when it corrects the unbalanced NO and ET-1.