[en] From the standpoint of radiological protection, the quantitative description of the physical characteristics and customs of man is the basis for calculating annual limit of intake, estimating dose equivalents and MIRD phantom for radioactive substances (ICRP 77). Committee 2 of ICRP has published compilation of data on the anatomical, chemical and physiological characteristics of man, as Standard Man and Reference Man. The models are, however, mostly based on the data published for Europeans and Americans. Reference Man, as characterized by the Task Group itself, is defined as a Caucasian and is a Western European or North American in habitat and custom. Reference Man, so far, is not directly applicable to other populations, for instance, the Japanese. Because it is known that differences exist between Asians, and Europeans and Americans with respect to race, customs and the pattern of food consumption. In view of this problem, it has become of necessity to seek standard or reference values for Japanese, i.e., mass and dimension of body and organs, and the daily intake, distribution, and metabolism of elements in Japanese, especially on the basis of more recently obtained data. Average mass of organs of the normal Japanese was studied and the results were presented for Reference Japanese Man. Development of chemical methods for determining stable elements in autopsy tissues was carried out to establish a highly reliable analytical system. Thyroidal uptake and biological half-life of ingested ¹³¹I in relation to the dietal stable element intake was determined for two normal Japanese adult male subjects. (author)