Background <p>This study explored the influence of children’s friendship on cyberbullying, incorporating the Belonging Hypothesis and the General Aggression Model. It examined the roles of Internet use frequency and online peer support in the relationship between friendship and cyberbullying. Friendship was considered the independent variable, while Internet use frequency and online peer support served as mediating variables, and cyberbullying was the dependent variable.</p> Methods <p>A survey was conducted among 1,016 children from grades 3 to 6 in two primary schools using the “Children’s Friendship Quality Questionnaire,” “Cyberbullying Behavior Scale,” “Internet Use Scale,” and “Online Peer Support Questionnaire.” To test the chain mediation model, 5,000 samples from SPSS Model 6 were used to estimate the 95% confidence interval of the mediating effect.</p> Results <p>Children’s friendships negatively predicted cyberbullying, and the frequency of Internet use mediated the relationship between friendship and cyberbullying. Notably, both Internet use frequency and online peer support were found to chain-mediate this relationship.</p> Conclusions <p>This study highlights several potential pathways between children’s friendships and cyberbullying while also emphasizing the dual nature of friendship. It holds both theoretical and practical significance for understanding the dynamics of friendship and cyberbullying and offers valuable insights for reducing cyberbullying behavior among children.</p>