The percentage of people aged 80 years or older in Japan has been increasing. The purpose of this study was to investigate the association between vascular functions and aging in the elderly population and to clarify the characteristics of vascular functions in subjects aged 80 years or older. We measured flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID), and brachial-ankle pulse wave velocity (baPWV) in 737 subjects aged 60 years or older who visited the outpatient clinic at Hiroshima University Hospital. FMD and NID were significantly lower in subjects aged 80 years or older than in subjects aged 60–69 years or in subjects aged 70–79 years (1.9 ± 2.0% vs. 2.9 ± 2.6% and 2.7 ± 2.6%, P = 0.008 and P = 0.03, respectively and 8.6 ± 5.1% vs. 12.1 ± 5.6% and 11.2 ± 5.5%, P < 0.001 and P < 0.001, respectively). baPWV was significantly higher in subjects aged 80 years or older than in subjects aged 60–69 years or in subjects aged 70–79 years (1978 ± 452 cm/s vs. 1724 ± 319 cm/s and 1811 ± 318 cm/s, P < 0.001 and P < 0.001, respectively). Age over 80 years was significantly associated with lower FMD (OR, 2.02; 95% CI, 1.19–3.42; P = 0.01), lower NID (OR, 3.62; 95% CI, 2.13–6.17; P < 0.001), and higher baPWV (OR, 3.48; 95% CI, 1.99–6.08; P < 0.001) after adjustment for other cardiovascular risk factors. Vascular functions, including endothelial function, vascular smooth muscle function, and arterial stiffness, were shown to be further impaired in subjects aged 80 years or older, suggesting that vascular functions continue to be impaired throughout life with aging.