Estimates suggest that around 20% of women may have experienced rape. Various misconceptions about rape (i.e., rape myths) are closely related to victim blaming. In our studies we tested the link between system justifcation, beliefs in biological origins of gender diferences, ambivalent sexism and beliefs concerning sexual violence. Study 1 was conducted among 433 Polish students. The sequential mediation analysis suggests that system justifcation predicts the level of rape myth acceptance through beliefs in biological origins of gender diferences and then hostile (but not benevolent) sexism. In Study 2, conducted among 197 Polish students, we tested the relationship between beliefs in biological origins of gender diferences and beliefs concerning sexual violence using experimental design. Contrary to our expectations, students who read the text about social origins of gender diferences perceived the survivor of a hypothetical acquaintance rape as less credible, and proposed a lower sentence for a stranger rape perpetrator, compared to participants who read about biological origins of gender diferences. We suspect that this is due to experiencing reactance when confronted with social explanations of gender diferences. We discuss implications for research and policy