Objective To investigate the correlation of arteriosclerosis obliterans (ASO) of the lower extremity with coronary artery disease (CAD) and stroke. Methods The clinical data of 587 elderly patients with lower extremity ASO hospitalized in our hospital from October 2013 to March 2021 were collected and analyzed retrospectively. Their incidences of CAD and stroke were investigated. The correlations of Fontaine ischemic stage and ankle brachial index (ABI) with CAD and stroke were analyzed with Spearman correlation analysis. SPSS statistics 26.0 was employed for statistical analyses. Results The incidence rates of CAD, stroke, and CAD complicated with stroke were 32.20% (189/587), 13.12% (77/587) and 17.21% (101/587), respectively in the 587 patients. The Fontaine ischemic stage in the lower extremity was positively correlated with the occurrence of CAD (r=7.57, P<0.01) and stroke (r=3.57, P<0.01), and number of cardiovascular and cerebrovascular diseases (r=0.13, P=0.02). There was significant difference in ABI between the patients with CAD and those without [0.30 (0.00,0.55) vs 0.68 (0.50,0.80)], and those with stroke and without [0.40 (0.15,0.62) vs 0.60 (0.20,0.75)] (both P<0.01). ABI value had a negative correlation with the number of cardiovascular and cerebrovascular diseases (r=-0.48, P<0.01). Conclusion The incidence of cardio-cerebrovascular diseases is quite high in the elderly patients with lower extremity ASO. The more severe the lower extremity ischemia is, the higher risk for cardiovascular and cerebrovascular diseases.