Sexist attitudes have traditionally been identified as a risk factor associated with violence against women, with male young offenders being a target population for prevention efforts. The main objective of this study was to evaluate the effectiveness of the “Intervention Program to Promote Egalitarian Relationships” aimed at reducing sexist attitudes in male adolescent offenders. A pre-experimental study was conducted involving 104 male adolescents aged between 14 and 21 years (M=17.35; ± 0.16) who were under judicial custody. Data on sexist attitudes were collected before and after participation in the intervention program using the Adolescent Sexism Detection Scale (DSA). The results revealed a significant reduction in both hostile and benevolent sexist attitudes, but only among those participants who displayed high levels of sexism at baseline. Conversely, participants with low levels of sexism prior to the intervention experienced a slight increase in hostile sexist attitudes. These findings demonstrated the usefulness of implementing programs targeted at reducing sexist attitudes in adolescent offenders, emphasizing the need to tailor interventions to the level of risk presented in order to maximize their effectiveness.