Aggressive behavior is the fourth leading cause of adolescent death in 2016 (Enopadria, 2018). The effects of aggressive behavior on adolescents include physical injuries, psychological injuries and social injuries. This aggressive behavior is not only in the form of physical aggression but can manifest in other forms such as angry behavior, verbal aggression, and show hostility to others (Hardoni, 2019). The purpose of this study is to analyze the aggressive behavior that occurs in adolescents, especially high school students in the Pekanbaru city. The population in this study were high school students in the city of Pekanbaru. The number of samples of this study were 904 adolescents. The sample technique used is accidental sampling. The research instrument uses the Brief Aggression Questionnaire. The results of a study conducted in 2020 on high school students in Pekanbaru city about aggressive behavior were 42.1% of adolescents showing low aggressive behavior, while another 57.9% showed high aggressive behavior. It is expected that educational sites will activate the PIK-R program at school because this program is expected to be one of the platforms to suppress aggressive behavior that can occur in adolescents or students in Pekanbaru and its surroundings.