Despite extensive research on cyberbullying, the interplay between gender, personality factors, and cyberbullying perpetration behaviours on social networking sites remains underexplored, particularly among young adults. This study aims to examine gender differences in cyberbullying perpetration on Facebook and, guided by the General Aggression Model as the theoretical framework, to explain how individual factors such as empathy, callous-unemotional traits, and moral disengagement, as moderated by the number of Facebook friends, contribute to cyberbullying perpetration on Facebook. This study investigates this complex association among a community sample of 171 participants aged 18 to 35 years (57.9% female), selected through convenience sampling and the snowball recruitment method. The findings revealed no significant interaction effects of the number of Facebook friends in the association between personality factors and cyberbullying perpetration on Facebook. More, results showed no significant gender differences in the frequency of cyberbullying perpetration. However, distinct gender patterns emerged in the association between personality traits and cyberbullying perpetration on Facebook. Males demonstrated stronger associations between moral disengagement, cognitive empathy, and cyberbullying perpetration on Facebook, while females exhibited significant associations between cognitive and affective empathy and cyberbullying perpetration on Facebook. The implications of these findings are thoroughly discussed in relation to existing literature.