Urinary di- and polyamines were analysed by gas-liquid chromatography in 63 normal volunteers. Subjects were divided into two age groups for each sex (males: from 18 to 40 years, and 40 to 70; females from 15 to 35 and 35 to 50), in order to establish age and sex dependent variations in the normal excretion of polyamines. Age appears to have some influence only in the excretion of spermine in male subjects. Sex on the contrary, has a considerable influence on urinary polyamines. Mean values of excretion for putrescine and spermine in female subjects are higher than those in males and show a wide variation in standard deviations.