In this study cadmium concentrations in several organs of more than 100 cadavers were measured in order to estimate the total body burden of cadmium by age. Six hundred urine samples from inhabitants of Tokyo of various age groups were collected in order to measure cadmium concentrations to observe if urinary cadmium concentration reflects the total body burden. The average renal cadmium concentration in the age group 40-49 years reached about 200μg/g (20mg net weight in the kidneys). However, individual variation was very great. The total body burden of cadmium was calculated to be about 45mg in the age groups 30-59 years. In general, cadmium concentrations in the organs and the total body increased with age, leveling off at about 60 years of age. The average cadmium concentration in urine was 1.7μg/l in all age groups, increasing by age and showing a pattern similar to that of cadmium concentrations in the total body according to age, and it was shown that on a group basis, cadmium in urine of the Japanese people reflected the total body burden of cadmium.