The purposes of this study are (1) to make scales of relationships between grandchildren in adolescence and grandparents, and (2) to clarify functions of grandparents perceived by grandchildren and functions of grandchildren perceived by grandparents. Subjects were 517 students in junior high schools, high schools and universities (mean of age: 17 years old), and 107 elderly persons at home (mean of age: 73 years old). As a result, factorial validity and reliability of the scales were confirmed. We found the functions of “daily emotional support”, “acceptance of existence”, “time perspectives”, and “succession of generations” in both the grandchildren scale and the grandparents scale. Additionally we identified the function of “instrumental informational support” in the grandparents scale. The fact that the functions of “time perspectives”, and “succession of generations” were found in two groups suggested the facilitation of mutual development between the generations. In addition, the function of “acceptance of existence” suggested possibilities of genuinely supportive relationships.