Based on a preliminary analysis of our written survey and interviews to Japanese parliamentarians, the current paper compares the similarities and differences between men and women’s office-seeking pathways to political representation in the Diet. The predominant party system, political party label, and the overwhelmingly majoritarian effects of the mixed parallel electoral system exert significant impact on both women and men office-seekers. Aggregate-level gender bias observed in other national contexts are likewise confirmed in our survey results. Building upon Jerome and Black’s (2000) methodological approach into the experiences and backgrounds of female and male office-seekers, we further disaggregate our results by political party and electoral system (PR vs FPTP). Through this second analysis, we discern more clearly the areas in which women and men’s policy interests, pathways to politics, and subsequently, their parliamentary activities reflect ‘similarity’ and ‘difference’ relative to men, and/or when and how office-seeking and elected women are still having to ‘compensate’ for their gender