--- - |2+ The present study utilized a laboratory paradigm to examine the extent to which bystander behavior for sexual aggression is independently and jointly influenced by situational misogynistic peer norms and men's adherence to hegemonic male norms. Participants were a racially diverse college sample of self‐identified heterosexual men (N = 104) between the ages of 18–35. Men completed a measure of hegemonic masculinity and engaged in a laboratory paradigm in which they and three male confederates watched a female confederate, who reported a strong dislike of sexual content in the media, view a sexually explicit film which they could stop at any time. Prior to the woman viewing the film, participants were randomly assigned to a peer norm manipulation wherein the male confederates set a misogynistic or ambiguous norm. Results indicated the presence of a misogynistic peer norm decreased the likelihood and speed of intervention. Among men exposed to misogynistic, compared to ambiguous, peer norms, men who strongly endorsed the status male role norm were less likely to display prosocial bystander behavior. Findings indicate that exposure to peers who sexually objectify and disrespect women decreases prosocial bystander intervention. Further, these findings provide evidence that misogynistic peer norms heighten men's adherence to a hegemonic masculinity that men should attain social status, thereby deterring bystander behavior for sexual aggression. - Aggressive Behavior, EarlyView.