Cyberbullying is a complicated and multifaceted phenomenon especially among youngsters, thus understanding the determinants of cyberbullying is prominent to explain what causes youngsters experience cyberbullying. Since little is known about the link between personality traits and cyberbullying, the current study aimed to explore the effects of vocational high school students' personality traits on their cyberbullying behaviors. In this regard, "Cyber victim/bully Scale", and "Adjective Based Personality Scale" were administered to 246 participant students. A structural regression model was developed with predictor variables and tested to see the effects of personality traits on cyberbullying. The goodness of fit indices indicated acceptable fitness (χ2/df:2.63, RMSEA: .08, GFI: .55, AGFI: .53, CFI: .61, IFI: .61). The results illustrated that openness is the strongest significant predictor of both cyberbullying (R2=-.83, p<.05) and being bullied (R2=-.77, p<.05). Yet another significant but positive predictor of cyberbully is extroversion (R2=.54, p<.05). However, the weakest positive significant predictor of cyberbully is agreeableness (R2=.14, p<.05). In addition to openness, conscientiousness was also found to be another significant predictor of being bullied (R2=.64, p<.05). Surprisingly, neuroticism has no significant effect on cyberbullying and being bullied.