Although blood pressure and age are major determinants of arterial stiffness, it is still unclear whether age-related changes in arterial stiffness are similar among subjects with different degrees of severity of hypertension. The present study examined the association between age and pulse wave velocity in subjects with different degrees of hypertension stratified according to the JNC-7 classification (Normal, Prehypertensive, and Stage I or II Hypertensive subjects). A number of 5,312 subjects (age range, 30-79 years) with no atherosclerotic risk factors other than high blood pressure were selected from two cohorts who regularly underwent annual health checkups, including the measurement of brachial-ankle pulse wave velocity (baPWV). baPWV was increased according to the severity of hypertension in all age groups. The association between age and baPWV formed a quadratic curve in each stage in both genders. The steepness of the slope of the quadratic curve increased according to the severity of hypertension. In each stage of hypertension, age and the baPWV were divided into tertiles. After adjustment for systolic and diastolic blood pressure, the odds ratio of having an increased baPWV in the 3rd age tertile (the highest-age group) was found to increase according to the severity of hypertension. In conclusion, the age-related increase of baPWV was shown to be augmented in phases according to the severity of hypertension, and this augmentation occurred even between the Normal and Prehypertensive stages. These results support the JNC-7 recommendations for a strict control of blood pressure even in the elderly.