In this study, interviews with single fathers, who are considered invisible in current society, were conducted in a semi-structured way, and the balancing of their roles as fathers and workers was investigated. The sampling number was eight and all the samples were single fathers living in urban areas with a child or children aged under 18. The sampling was carried out by network-sampling through an NPO supporting single fathers. All the collected data were divided into two groups depending on whether or not the samples lived with parents able to share the burden of child-raising, and the data were analyzed with the constant comparative method. The results showed that housework and child-rearing skills are required as necessary resources at home, and all the fathers who lived independently of their parents have acquired these skills. The need for these two skills decreases slightly in the case of those living together with their parents, although these fathers have concerns about declining support from their father and/or mother. In terms of career roles, fathers living apart from their parents focus on advanced scheduling in order to receive maximum support from their parents as well as from the public, and therefore a work environment that facilitates making advanced schedules is an important resource for them. On the other hand, fathers who share the burden of child-raising with their parents pay attention to the politics of the company they work for so as to gain an understanding of their coworkers in order to fulfil their parental roles. Finally, for both groups, the sense of a single father and management skills to create suitable conditions for child-rearing are essential in order to accomplish their roles as both a worker and a parent. In addition, it was found that a single father has a unique identity structured by family role, work role, and masculinity.