In 500 human fresh cadavers (250 males and 250 females) the corrected circumference has been measured of the following arteries: aorta, coronary arteries, branches of the aortic arch, arteries of the base of the brain, iliac arteries. Elaborating these data by a computer, the following age power function, expressing the arterial circumference, has been found: y = Kxn less than 1, being y the corrected circumference, x the age and K and n constants, specific for each artery. By means of this equation the inconstancy of the measured data has been suppressed. The statistical elaboration has given the following results: 1. No evidence has been found on a statistically significant difference between male and female arteries, even if the male sex has generally vessels a little larger than the female sex. 2. No evidence has been found on a statistically significant difference between right and left arteries, even if, generally, the right vessels are a little larger than the left ones. On the other hand, for the coronary arteries and for the vertebral arteries, the left side is prevalent. 3. As a general statement, there is evidence that the arterial circumference of considered vessels increases with ageing.