PURPOSE: The size of prostate increases with age, but there has been few Korean data on the prostate size in the general population. We thereby report the size of prostate with respect to age in Korean men residing in Namhae, Korea. MATERIALS AND METHODS: To determine the prostate size, 1421 men from Namhae, Korea underwent transrectal ultrasonography. Size of the prostate was estimated as a weight by the elliptical method. RESULTS: The mean prostate weight was 33.5 10.6 ml. The relationship between prostate volume and age was statistically significant in 1421 men (Pearson correlation coefficient=0.156, p=0.0001). Also, between the normal group and the groups of men with lower urinary tract symptoms (LUTS), there was significant correlation with age (Pearson correlation coefficient=0.162, p=0.0001), while results were insignificant with size (Pearson correlation coefficient= 0.170, p=0.0001). CONCLUSIONS: Size and rate of growth of the prostate were smaller compared to the Western society, nevertheless, prostate size increased with age. For accurate and reasonable age-specific size of the prostate of Korean male, more community based multicenter study will be needed with more refined measurement techniques such as step-section planimetry for the prostatic volume estimation.