Cyberbullying has been subject to a debate about whether it is a subtype of traditional bullying or a distinct deviant behavior from traditional bullying. Applying a longitudinal South Korean youth sample and latent group-based trajectory modeling, the current study examines (a) an overlap of developmental trajectories between cyberbullying and traditional bullying, and (b) effects of predictors on developmental trajectory groups for both cyberbullying and traditional bullying. It is concluded that cyberbullying is close to a variation of bullying rather than a distinct deviant behavior and reported an overlap of developmental trajectories between cyberbullying and traditional bullying, and strong associations between both forms of bullying and peer-related predictors. Policy implications and suggestions for future research are discussed.