To investigate the clinical effects of Erxian Dihuang Decoction combined with insulin in the treatment of type 2 diabetes mellitus(T2DM)and its effects on blood lipid，endothelin-1(ET-1)，blood glucose and hemorheology. Methods:A total of 96 patients with T2DM were selected from June 2015 to February 2016 and randomly divided into the control group(n=48)and the observation group(n=48)according to random number table method. The control group was treated with insulin hypoglycemic therapy，while the observation group was treated with Erxian Dihuang Decoction on the basis of the control group. Both groups received continuous treatment for 4 weeks. The clinical efficacy of the 2 groups was calculated. The changes of blood lipid，ET-1 level，blood glucose and hemorheology indexes in the 2 groups were detected and compared. Results:The total effective rate of the observation group was 95.83%，which was significantly higher than that of the control group(83.33%)(P<0.05). After treatment，the blood lipid levels of TC，TG，LDL-C and other indicators in the 2 groups，as well as the blood glucose levels of ET-1，FPG，2 hPG and HbAlc，were significantly decreased and HDL-C was significantly increased(P<0.05 or P<0.01). The differences between the 2 groups were significant(P<0.05 or P<0.01). After treatment，the whole blood viscosity，plasma viscosity，erythrocyte specific volume and erythrocyte rigidity indexes of the 2 groups were significantly decreased while the erythrocyte deformation index was significantly increased(P<0.05 or P<0.01). The differences between the 2 groups were significant(P<0.05 or P<0.01). Conclusion:Erxian Dihuang Decoction combined with insulin has definite clinical effects on T2DM patients. It can effectively reduce the blood glucose and lipid levels of patients as well as relieve the hypercoagulation state of blood and reduce the levels of ET-1，contributing to the recovery of the disease.