Mortalities from selected causes from 1973 to 1982 among Koreans, Chinese, and Americans residing in Japan were compared with those of Japanese. In the Korean population, besides the well-documented excess in mortalities from liver cancer, lung cancer, liver cirrhosis and male tuberculosis, a rather prominent elevation was observed for mortalities from female tuberculosis and diabetes mellitus in both sexes. Distinctive features in the Chinese population were increased mortalities from liver cancer and female lung cancer and lowered mortality from stomach cancer, and these findings are consistent with the observations among Chinese in other areas. Mortalities from diabetes mellitus and liver cirrhosis was moderately increased in this population as well. Americans in Japan by and large showed a mortality pattern similar to that in the US although mortality from stroke among female Americans was rather elevated during the period 1973-1977. Epidemiological studies on Koreans and Chinese in Japan with reference to their lifestyle are strongly required.