The present study aims to value the relationships between reactive/proactive aggression and cognitive distortion among adolescents from Arequipa City in Peru, in order to it was necessary to practice a psychometrical analysis of the tests used. In that sense there were evaluated 2830 high school students (48.9% female and 51.1% male) aged 13 and 19 years old, with Reactive/Proactive Aggression Questionnaire and the How I Think Questionnaire. The psychometrical analysis included the estimation of the validity and reliability of the instruments applied, so as the correlation analysis to determine the relation between the variables. The psychometrical results shown that the construct validity and the reliability of the questionnaires, have good fit values and internal consistency; while the correlation analysis reveal that the reactive aggression is weakly related with cognitive distortions, and proactive aggression is related y moderate way cognitive distortions.