<p>Sexual violence against women is one of the serious problems globally. While there is significant research on this topic in Western settings, there is insufficient knowledge and understanding of the problem in Japan. Due to low reporting rates of sex crimes in Japan, there is a scarcity of characteristics of Japanese sex crime perpetrators. Therefore, it is crucial to identify risk factors for sex crimes to prevent them before they are committed. In Western countries, cognitively distorted thinking about targets, cultural factors, such as patriarchal beliefs, have been associated with an increased risk of committing sexual violence. Although those risks are identified in Western settings, there is no research that has examined how those variables have been linked to sexual violence against women in Japan. This study explored the associations among patriarchal belief, cognitively distorted thinking toward women, and notions of rape myth acceptance among 234 Japanese males recruited through an online questionnaire platform and found a significant correlation between patriarchal belief and rape myth acceptance. Further, this study found that younger men had significantly higher cognitive distortions than older participants. Moreover, employment status was significantly influenced by patriarchal beliefs; that is, individuals who are working as salarymen significantly scored higher on patriarchal beliefs than the unemployed group. Overall, like Western countries, irrational beliefs about women and patriarchal norms increase the risks and acceptance of sexual violence against women among a Japanese male sample. These results were reviewed in order to identify risk factors that could help improve the primary prevention of sex crimes in Japan.</p>