This study was conducted to examine differences across age groups in the degree of satisfaction with life. A total of 1,067 participants (145 middle school students, 135 highschool students, 184 university students, 465 adults, and 138 older adults) took part in the study. The participants responded to a questionnaire which consisted of two scales: the Satisfaction with Life Scale developed by Diener et al.(1984) to assess their overall life satisfaction, and a scale to assess their satisfaction in each of four domains of life. Physical, material, social, and productive domains of life were extracted from factor analyses. The findings of the present study were as follows. First, overall satisfaction with life was the highest for the older adults and the lowest for the highschool students. A similar pattern of the results was obtained for satisfaction in material, social, and productive domains of life, whereas not the older adults but the middle and university students were found to be the most satisfied in the physical domain. Second, among all the demographic variables examined, socioeconomic status had the greatest influence on the level of satisfaction in the four domains of life as well as overall satisfaction with life. Third, the age variable was found to interact with several other demographic variables: They were gender by age interaction in satisfaction with social relationships and productivity; education level by age interaction in the overall life satisfaction and satisfaction with physical health; and family type by age interaction in material satisfaction and satisfaction with social relationships. Finally, for the younger as well as the older people, satisfaction in material and productive domains had great influences on their overall satisfaction with life, whereas satisfaction in physical and social domains had relatively little effects. The implications of these results were discussed.