The activity and growth of the accessory male sex gland depend on the androgen. The sex hormones effect on the growth of seminal vesicle and the prostate differently, but the relationship of the age and hormonal effect is not clear. To clarify the ageing effect on the male sex accessory gland, the morphometrical study has been done and the results analyzed with hormonal effect on the gland structure. Twenty-five seminal vesicle and prostate on bloc autopsy specimens[aged 22-68] were used. Middle portion of each side of the seminal vesicle and all blocks of the prostate horizontally divided at 3-5mm were embbeded in paraffin. Serial 7microm thick sections were prepared with hematoxiline and eosin, Gomori trichrome staining. For quantification, the image analyzer and the point counting method were used. There was not noticable change in the ratio of the parenchyma and the fibromuscular stroma in prostate until age of 60. At age of 20s, the actual ratio of the central, peripheral and transitional zone was accounted to 25%, 70%, 5% respectively, and it changed to 25%, 62%, 13% at 50`s. The percentage of the epithelial component in the glandual tissue was higher in the seminal vesicle. In the prostate, that was highest in the central zone. Stromal component was most abundant in the transitional zone. In both glands, the epithelial percentage decreased while the stromal percentage increased with age. The changing rate of the epitheilal and stromal compoenent was highest in the central zone. The luminal component changed only in the peripheral zone. The stromal component was most abundent in the transitional zone at all ages, even the increasing rate was highest in the central zone. The change in the proportion of each prostate zone and the different pattern of tissue compositional change in seminal vesicle and each prostate zone according to age represent the difference of hormonal and ageing effects on the seminal vesicle and each prostate zone.