Objective To observe effects of Huanglian Jiedu Decoction on fasting blood glucose (FBG), fasting insulin (FINS), abdominal aortic morphology and expression of HIF-1α in the abdominal aorta in rats with type 2 diabetes. Methods The rat model of type 2 diabetes was established by intravenous injection of streptozotocin and feeding with high sugar and high fat diet. Rats were randomly divided into blank group, model group, control group and treatment group. The blank group and model group were given normal saline by gavage, the control group was given metformin, and the treatment group was given Huanglian Jiedu Decoction. Six weeks later, the levels of FBG and FINS were determined. Immunohistochemical method was used to determine the expression of HIF-1α in abdominal aorta and HE staining method to observe the changes of abdominal aortic morphology. Results Compared with model group and control group, abdominal aorta of HIF-1α and FBG level of treatment group were significantly decreased (P <0.01), FINS significantly increased (P <0.01), and abdominal aortic endothelial cell injury was significantly improved. Conclusion Huanglian Jiedu Decoction has a protective effect on the injury of vascular endothelium, and its mechanism may be related with inhibiting the expression of HIF-1α.