© 2019 Elsevier Inc. Life satisfaction (LS), as a major indicator of subjective well-being, is a rapidly growing concern all over the world. Despite their country's powerful economic status, Japanese people experience relatively low levels of LS. This paper investigates demographic, social and psychological variables associated with Japanese people's life evaluation, and identifies important factors in each age and gender group. Using a representative annual survey of Japanese respondents, we find that material well-being (household income satisfaction, satisfaction with standards of living) is most strongly associated with LS. Other factors such as marital status, affective experience, and education, are also significant predictors. The data show that LS decreases over the life course and that individuals in late adulthood are the least satisfied with their lives. Furthermore, there is evidence that a gender gap exists for levels of LS at each stage of life. We identify important factors associated with LS across gender and age groups and, overall, our intensive analysis of a wide range of potential factors provides a comprehensive model of life evaluation in Japan. We conclude with the argument that follow-up studies will benefit from a consideration of key social issues in the context of Japanese society such as relative wealth, ageing, and gender inequality.