The paper investigates why political representation of women in the Japanese Diet has not progressed as anticipated. Although Womenomics policies have been implemented successfully by the government in recent years in Japan, it has been argued that Womenomics policy does not adequately addressother aspects of female representation, including women’s political participation. To examine this, the current study, which is based on a qualitative research method, used semi-structured interviews with women MPs from several different political parties in Japan and with academics specializing in women’s issues and Japanese politics. Based on these interviews, it was noted that the patriarchal social structure still prevalent in Japan was the main barrier to understanding the significance of women’s political representation in Japan, suggesting that there has been no advancement in the representation of women in politics as a result of an inability to appreciate the value of women’s involvement in politics. However, an ongoing failure to remove the barriers that prevent women who are interested in politics from taking part in political life from doing so is anotherreason why women’s political representation has not improved in Japan. Component investigation of this can be assessed across three stages. Women’s interest in politics is the first of these, as women specifically strugglewith issues such as a lack of family and spousal support. In the second stage, the systemic limitations that affect women’s political decisions and interests, include the extreme overworking culture in Japan and the lack of female role models in politics must be considered. The male-dominated political system and party structures that effectively prevent women from participating in politics after they have passed the first two stages of entry to the Diet must then be seen as a third set of barriers.