In the literature on Japanese personnel management or work-life balance, there have been numerous arguments until now about working hours which is regarded as one of a basic variable. Those studies are naturally important since they have clarified several findings on working hours. However, various other studies have asked us to think about the following question “why reduction of working hours is important ?” The answers to the abovementioned question reinforce the arguments about working hours. Odaka's theory serves as a reference while analyzing this problem. According to Odaka's theory, our occupation is an activity that aims at not only maintaining livelihood but also demonstrating self-ability and attaining solidarity (Odaka  1995). Therefore, we can say that workers, in working time, also are able to display their abilities and get solidarities in the society. As per these viewpoints, it is also important to reexamine whether long working-hours have bad influences on the well-being of workers. Therefore, in this study, I examine the direct and indirect effects of working hours on well-being. In the analysis section, this study mainly employs the diagram that added the variables of cooperative work in addition to the variables frequently discussed in the study of job satisfaction. The following are the salient findings of this study: firstly, the length of working hours has a direct negative effect on the subjective well-being of workers to some extent; secondly, the length of working hours also has an indirect effect on the subjective well-being of workers. In particular, as the working hours become long, variables that weaken the effect on subjective well-being appear. The latter findings especially indicate an important possibility that as working hours become long, the occupational perspective of workers becomes narrow, namely, the meaning of occupation for the workers becomes poor.