The brachial-ankle pulse wave velocity (PWV) is a quick test which adequately estimates arterial stiffness. Because flow-mediated dilatation (FMD) of the brachial artery assesses an essential endothelial function, we tested the hypothesis that the brachial-ankle PWV could reflect the early stages of endothelial dysfunction caused by smoking in young, healthy subjects. Fifty-seven healthy subjects (13 females and 44 males; mean 29.9+/-5.6 years) were enrolled. Twenty-six of the subjects (30.4+/-5.7 years) were active smokers, with a mean cumulative nicotine consumption of 10.0+/-8.6 pack/years, and thus were assigned to the smoking group. Thirty-one subjects without a history of smoking (29.5+/-5.5 years) were assigned to the non-smoking group. The brachial-ankle PWV and arterial blood pressure were simultaneously measured using a recently established, non-invasive automatic device (model BP-203RPE; Nihon Colin, Tokyo, Japan). Endothelium-dependent FMD was induced by reactive hyperemia, while endothelium-independent vasodilation of the brachial artery was induced by administration of sublingual nitroglycerin spray. The FMD was lower in the smoking group than in the non-smoking group (p<0.05). There was no significant difference between the two groups with respect to the brachial-ankle PWV. In the non-smoking group, multiple stepwise regression analysis revealed that FMD was predicted by the systolic blood pressure (F=16.351). In the smoking group, statistical analysis revealed that FMD was independently predicted by either the brachial-ankle PWV (F=8.108) or the subject's age (F=4.381). Our results suggest that a reduction in FMD is closely associated with the early stages of endothelial dysfunction caused by cigarette smoking in young, healthy subjects, which is at least partly reflected by the PWV value.