Objective To investigate the therapeutic efficacy of modified Buyang Huanwu Decoction in the treatment of type 2 diabetes mellitus(T2DM)patients with peripheral neuropathy of qi deficiency and blood stasis type,and to observe its effects on serum fibroblast growth factor 21(FGF21),25-hydroxyvitamin D[25(OH)D],endothelin 1(ET-1)levels and hypercoagulable state of the patients.Methods A total of 124 T2DM patients with peripheral neuropathy of qi deficiency and blood stasis type who admitted to Haikou Hospital of Traditional Chinese Medicine from December 2019 to December 2022 were randomly divided into a control group and an observation group,with 62 cases in each group according to the random number table method.The control group was treated with conventional western medicine,and the observation group was treated with modified Buyang Huanwu Decoction on the basis of treatment for the control group.The course of treatment for the two groups covered 12 weeks.The changes of traditional Chinese medicine(TCM)syndrome scores,blood glucose indicators,hemorheology indicators,nerve conduction velocity(NCV)and levels of serum FGF21,25(OH)D,ET-1,interleukin 6(IL-6)in the two groups before and after treatment were observed.After treatment,the therapeutic efficacy of the two groups was evaluated.Results(1)After 12 weeks of treatment,the total effective rate of the observation group was 96.77%(60/62)and that of the control group was 83.87%(52/62),and the intergroup comparison(tested by chi-square test)showed that the therapeutic efficacy of the observation group was significantly superior to that of the control group(P<0.05).(2)After treatment,the total TCM syndrome scores and the scores of TCM symptoms such as limb pain,hypoesthesia,excessive eating with frequent hunger,and limb numbness in the two groups were decreased when compared with those before treatment(P<0.05),and the decrease in the observation group was significantly superior to that in the control group(P<0.05).(3)After treatment,the levels of hemorheology indicators such as hematocrit,whole blood viscosity at high-shear rate,and plasma viscosity in the two groups of patients were decreased when compared with those before treatment(P<0.05),and the decrease in the observation group was significantly superior to that in the control group(P<0.05).(4)After treatment,the motor conduction velocity of the common peroneal nerve and the median nerve in the two groups of patients was increased when compared with that before treatment(P<0.05),and the increase in the observation group was significantly superior to that in the control group(P<0.05).(5)After treatment,the serum levels of blood glucose indicators such as fasting blood glucose(FBG)and glycosylated hemoglobin(HbA1C)in the two groups of patients were decreased when compared with those before treatment(P<0.05),and the decrease in the observation group was significantly superior to that in the control group(P<0.05).(6)After treatment,the serum FGF21,ET-1,and IL-6 levels in the two groups were decreased(P<0.05),and serum 25(OH)D level was increased(P<0.05),and the decrease of serum FGF21,ET-1,and IL-6 levels as well as the increase of serum 25(OH)D level in the observation group was significantly superior to that in the control group(P<0.05).Conclusion For T2DM patients with peripheral neuropathy of qi deficiency and blood stasis type,the combination of modified Buyang Huanwu Decoction with conventional treatment in western medicine is helpful for reducing the inflammatory response,alleviating the damage of vascular endothelial function,regulating the levels of blood glucose,improving the neurologic function,and enhancing the clinical efficacy.