<p>The relationships among moral identity, moral disengagement, school climate, and cyberbullying perpetration among vocational college students remain insufficiently understood, particularly with the role of school climate within these associations. This study investigates the contested role of school climate in the associations linking moral identity, moral disengagement, and cyberbullying perpetration by comparing two competing conceptual models: one model conceptualizes school climate as a contextual (input) variable, while the other treats it as a moderator in the association between moral disengagement and cyberbullying perpetration. A cross-sectional survey was conducted with 625 vocational college students in Guangdong Province, China. Participants were 65.9% female, and most were aged 18–20 years (72.1%). The data were analysed using structural equation modelling and moderated mediation analyses. Results indicate that moral disengagement fully mediates the association between moral identity and cyberbullying perpetration, suggesting that cognitive justificatory processes transmit personal moral values into harmful online behavior. Comparative model tests supported the model 1, demonstrating that school climate exerts a direct contextual influence on cyberbullying perpetration but does not moderate the association between moral disengagement and cyberbullying perpetration. These findings help clarify the distinction between situational antecedents and cognitive mediators in the etiology of cyberbullying perpetration. This study contributes to an ongoing debate in the literature by clarifying the functional role of school climate in the interrelations among moral identity, moral disengagement, and cyberbullying perpetration.</p>