Background: One of the required conditions for creating and maintaining a satisfactory social relationship is the ability to regulate and control individual behavior in ways that meet the others’ needs and feelings, and when they are angry, they cannot harm anyone and control themselves, which called this behavior as Self-control. The main aim of this research was to determine the effectiveness of teaching the ethics of self-control on reducing aggression of the secondary high school male students of Yazd province.
Method: The Method of this research was semi-experimental study with pretest - posttest plan. The statistical population of this study includes all male students in the first grade high school of education in 2016-2017. 30 students were selected and randomly divide into two experimental and control group and each groups include 15 students. The instrument of this study was Bass and Perry questionnaire. Finally, the collected data were analyzed by using covariance analysis.
Results: The findings of this research showed that there were significant differences between the two experimental and control groups in the regarding with scores for all dimensions of aggression (physical, verbal, anger and  hostility). Self-control ethics training had a meaningful effect on students' aggression reduction.
Conclusion: In a general, we conclude that considering the high prevalence of aggression among male students in the first grade high school who are adolescents, Self-control ethics training can be an appropriate interventional strategy to reduce their aggressiveness.