It is well-known that aerobic exercise training beneficially affects endothelial function as measured by brachial artery flow-mediated vasodilation (FMD). This trial with older sedentary overweight and obese men, therefore, examined the effects of aerobic training on other non-invasive markers of the vasculature, which have been studied in less detail. Seventeen men (67 ± 2 years, BMI: 30.3 ± 2.8 kg/m² ) participated in this controlled cross-over study. Study participants followed in random order a fully supervised, progressive, aerobic exercise training (three 50-min sessions each week at 70% maximal power) and a no-exercise control period for 8 weeks, separated by a 12-week wash-out period. At the end of each period, endothelial function was assessed by the carotid artery reactivity (CAR) response to a cold pressor test and FMD, and local carotid and regional aortic stiffness by the carotid-to-femoral pulse wave velocity (PWV_c-f ). The retinal microvasculature, the serum lipid profile, 24-h ambulatory blood pressure, and 96-h continuous glucose concentrations were also determined. Aerobic training increased CAR from 1.78% to 4.01% (Δ2.23 percentage point [pp]; 95% CI: 0.58, 3.89 pp; p = 0.012) and FMD from 3.88% to 6.87% (Δ2.99 pp; 95% CI: 0.58, 5.41 pp; p = 0.019). The stiffness index β₀ increased by 1.1 (95% CI: 0.3, 1.9; p = 0.012), while PWV_c-f did not change. Retinal arteriolar width increased by 4 μm (95% CI: 0, 7 μm; p = 0.041). Office blood pressure decreased, but ambulatory blood pressure, and serum lipid and continuous glucose concentrations did not change. Aerobic exercise training improved endothelial function and retinal arteriolar width in older sedentary overweight and obese men, which may reduce cardiovascular risk.