Introduction: Adolescence is recognized as a particularly stressful period of development. During this period adolescent simultaneously deal with physical and cognitive transformations. Therefore, main of this study is the effects of life skills training on emotional reactions in boy adolescents in Tehran city..Methods: This is a semi – experimental study. In order to, the middle students in two schools in Tehran city (n=172) were chosen then we used DASS21 questionnaire to determine students with middle range of emotional reaction and then were divided to two group randomly, Finally 30 subjects in experimental and 30 in control group participated in this study.Then 30 students of control group trained life skills in five sections during two weeks. After 6 week experimental and control group responded to questionnaire..Results: Analysis of the entire study group before and after training, revealed significant difference in stress and anxiety and total emotional reaction but insignificant difference in depression..Conclusion: According to this study, life skills training reduce stress, anxiety and total emotional reaction in adolescents.