Abstract

• This study aimed to investigate the effect of peer pressure and self-control on aggression of high school students in Monywa Township. A total of 400 high school students (203 males, 197 females) in Monywa Township were randomly selected as participants of this study. Correlational research design and survey method were used in this study. Both descriptive and inferential statistics were carried out. Three instruments: Peer Pressure Inventory (PPI), Self-Control Scale (SCS), and Aggression Questionnaire (AQ) were used. According to the findings of this study, the result of independent samples t test revealed that there was no significant difference in peer pressure by gender. However, it was found that there was significant difference in peer pressure by grade (t = -3.171, p < 0.01). The result also stated that there was no significant difference in self control by both gender and grade. Moreover, the result of independent samples t test pointed out that there was no significant difference in aggression by both gender and grade. Then, the result of mediation analysis proved that peer pressure had significant direct effect on aggression and also significant indirect effect on aggression through self-control as a mediator. Totally, 31.4 % of the variance in aggression can be explained by the model.