The authors investigated the adaptability of Average Death-Age and Age-Adjusted Average Death-Age as a health indicator, mainly in comparison with some health indicators such as corrected death rate, average life span and infant death rate in several regions with various sizes of population ; the whole country, the prefectures and the regions covered by each Health Center in Iwate Prefecture. The results obtained were as follows : (1) The longitudinal changes of Average Death-Age for 15 years (1950-1965) in the whole country were very similar to the trends of average life span. (2) In the case of prefectures, Average Death-Age were sometimes valid but Age-Adjusted Average Death-Age was more reliable as a health indicator. (3) In the regions covered by a Health Center, Age-Adjusted Average Death-Age was also a useful health indicator but Average Death-Age was a useless one. Meanwhile, Average Death-Age and Age-Adjusted Average Death-Age are considered to cover the aspect of health level which can not be expressed by another health incators such as corrected death rate, infant death rate etc. Moreover, the calculations of these health indicators are rather simple in its procedure and the collection of necessary basic data can be easily done. Judging from the results and the facts mentioned above, these two health indicators, especially Age-Adjusted Average Death-Age, will be one of the most useful health indicators in each region with various sizes of population.