Objective: To explore relationship between heart rate variability (HRV) and lower extremity arterial disease (LEAD) in aged patients with type 2 diabetes mellitus (T2DM) and their clinical significance. Methods: A total of 65 T2DM inpatients with age 60~65 years were enrolled. According to LEAD condition, they were divided into T2DM + LEAD group (LEAD group, n=36), T2DM without LEAD group (NLEAD group, n=29) ，besides, normal control group was set up (n=23). The 24h dynamic electrocardiography was performed. Indexes of HRV were measured; meanwhile, blood pressure, indexes of glucose and lipid metabolism, CRP and plasma adiponectin were measured in all groups. Correlation analysis and multi-factor Logistic regression analysis were performed. Results: (1) Levels of SBP, HbA1c, LDL-C, CRP in LEAD group and NLEAD group were significantly higher than those of normal control group (P<0.05). Compared with NLEAD group, there were significant increase in course of disease [(3.00±2.00) years vs. (7.50±4.00) years], SBP [(140.24±8.95)mmHg vs. (147.61±7.58)mmHg], HbA1c [(6.40±0.70)% vs. (7.15±2.05)%], plasma fibrinogen（Fg）[(2.57±0.51) g/L vs. (3.02±0.71) g/L], LDL-C[(2.27±0.50) mmol/L vs. (2.81±0.71) mmol/L] and CRP[(2.01±1.79) mg/L vs. (3.14±2.92) mg/L] in LEAD group, P<0.05 all; (2) SDNN, SDANN, VLF and plasma concentration of adiponectin in LEAD group and NLEAD group were significantly lower than that of normal control group (P<0.05 all); Compared with NLEAD group, there were significant decrease in other indexes except rMSSD in LEAD group, P<0.05 all; (3) Spearman rank correlation analysis indicated that LEAD was positively correlated with course of disease, SBP, 2hPG, HbA1c, LDL-C, Fg, CRP (r=0.311~0.760, P<0.05 all), and negatively correlated with adiponectin and HRV indexes (r=-0.597~-0.317, P<0.01 all); (4) Multi-factor Logistic regression analysis indicated that course of DM, SBP, HbA1c, LDL-C, CRP were independent risk factors for LEAD in aged T2DM patients (OR=2.932~14.404, P<0.05). Conclusions: 1. The course of DM, SBP, HbA1c, LDL-C, CRP, adiponectin and HRV are related with LEAD in aged T2DM patients ; 2. Decreased HRV is an independent risk factor of LEAD in aged T2DM patients.