Abstract The aim of the study was to identify the direct and indirect existing relationship among personality traits on aggression of high school and undergraduate students from the city of João Pessoa, Brazil, using the General Aggression Model as the theoretical framework. The sample consisted of 218 students, of which 107 were high school students and 111 undergraduate students. The instruments used for data collection were as follows: Aggression Questionnaire, the Big Five Inventory and a Socio-Demographic Questionnaire. The main results showed direct effects of neuroticism (+), extraversion (+) and agreeableness (-) in physical aggression. On the other hand, indirect effects of neuroticism (+), opening (+) and agreeableness (-) in physical aggression, mediated by aggressive emotions have been found. These findings are discussed based on previous research and the General Aggression Model along with suggestions of research which have been conducted in an attempt to further knowledge in this area.