The purpose of this paper is a) to make a comparative study of the existence of ikigai (reason(s) for living) in elderly people and its relevance to their family structure, physiological situation and functional capacity in both rural areas and metropolitan suburban areas, and b) position basic research into the structure of ikigai in the near future, by clarifying several related factors, from which the concept of ikigai may be defined. The meaning of the word "ikigai" in Japanese is difficult to express exactly, and specialists in gerontology have varying definitions. If ikigai were translated from Japanese into English, it could be "reason(s) for living", "self-actualization", "meaning of life" and/or "purpose in life". In this paper, ikigai is used to mean "feeling of being alive now and/or individual motivation for living". As of October 2000, we studied 1,544 people aged 65 years and over living in town Y of Niigata Prefecture (rural area), and as of January 2001, we studied 1,002 people in the same age group in town H of Saitama Prefecture (metropolitan suburban area). The above investigations revealed the following characteristics:--(a) Regarding the percentages of persons having or not having ikigai, there were no significant differences between the rural area and the metropolitan suburban area. (b) In both areas, the 3 factors of self-rated level of health, intellectual activeness and social roles, were associated with having ikigai. (c) In the rural area, the family structure was strongly associated with having ikigai, but gender or generation were irrelevant. (d) In the metropolitan suburban area, the hospitalization experience of men was strongly associated with ikigai. Furthermore, there was a strong correlation with generation. In this regard, while the contents of ikigai are seldom examined in detail, clarification of the structure of ikigai should be worked out in the next stage of the study, using covariance structure analysis. In addition the development of concrete plans to promote ikigai by municipal organs could be beneficial.