〔Abstract〕 Objective To investigate the expression of miR-155 in peripheral blood of type 2 diabetes patients(T2 DM) associated with diabetic foot ulcer(DFU) and its relationship with the onset of DFU. Methods Sixty newly diagnosed T2 DM patients without DFU(T2 DM group), 112 T2 DM patients with DFU(DFU group), and 60 healthy controls with normal glucose tolerance(NC group) were included. MiR-155 levels were determined by quantitative real-time PCR, while clinical features and risk factors of DFU were explored. Results A significant decrease in the expression level of miR-155 in peripheral blood was observed in T2 DM group compared with NC group(P<0.05), and a markedly increased miR-155 expression level was noted in DFU group compared with T2 DM group(P<0.01). Moreover, there was a positive correlation between the expression level of miR-155 in peripheral blood and the course of foot ulcer and Wagner grade of foot ulcer(P=0.02,P=0.01) while a negative correlation in the expression level of miR-155 with healing rate of DFU after eight weeks(P=0.04). The multiple stepwise logistic regression analysis confirmed that a high expression of miR-155 was an independent risk factor for DFU(OR=3.98,P=0.002). Conclusion An increased expression of miR-155 in peripheral blood of T2 DM patients is an independent risk factor for DFU and is closely related to the prognosis of DFU.