The purpose of this study was to investigate the relations among usage of slang, aggression and self-control, to examine the mediating effects of self-control. For the purpose of this study, the subjects was consist of adolescents in the region of K city. The final 780 questionnaires were used as research data. The data analysis used correlation analysis, mediating effect through of regression analysis. The results showed usage of slang, aggression and self-control were significantly correlated, usage of slang had a direct effect on aggression. In addition, the result is analyzed in each gender. The total adolescents’ self control had partially mediating effects between usage of slang and aggression. Otherwise, female adolescents’ usage of slang had not a significantly effect on aggression. As a result in order to decrease the level of adolescents’ aggression and usage of slang, institutional intervention is required for healthy play activities and social improvement program. Finally, this study ends up with the implications of the study results, limitations and future research directions.