The present study was conducted to evaluate the influences of age and gender on the results of noninvasive brachial-ankle pulse wave velocity (baPWV). In 12517 subjects who had no medication and no history of cardiovascular diseases, multiple regression analysis demonstrated that age, blood pressure, body mass index, triglycerides, blood glucose, and uric acid were significant variables for baPWV in both genders. From this population, we extracted 7881 "healthy subjects" (4488 males and 3393 females, 25-87 years) without any of the atherogenic risk factors, and the results of baPWV were analyzed chronologically in 5-year age intervals. baPWV was lower in females than in males until age 60, and became similar in both genders over age 60. Multiple regression analysis demonstrated that not only the value of R(2) but also the coefficient of the effect of age on baPWV are larger in females than in males. In the estimation of the regression curve, the relationship between age and baPWV demonstrated a quadratic curve in both genders. Thus, aging influences baPWV, and its effect is more prominent in female. Menopause seems to be the crucial phenomenon to explain the augmented increase in arterial stiffness with aging in females.