This paper presents data concerning culturally prescribed gender traits and their influence on bullying/victimization problems and aggressive tendencies from a wide sample of 1,654 Spanish adolescents. The aims of this study were to clarify the effect of masculine traits on male and female secondary students' aggression, and also to explore the role of feminine traits in either the inhibition of aggression or the use of more covert forms. Results show that masculine stereotypical traits are related more strongly with bully perpetration, proneness to aggression and experience of anger and hostility in both sexes. In contrast, traditional feminine traits are negatively related with bullying perpetration and proneness to aggression. However, feminine traits are linked to male students' victimization. Results are discussed in the light of previous findings and are taken into consideration in the design of intervention practices in secondary schools.