Aim and Background: School is where adolescents spend a great part of the day in it. If the influencing aspects of it are known, school could be used as a context for preventive programs. Factors related to tendency toward cigarette, alcohol and drug use investigated in this study.Method and Materials: In a descriptive crosssectional study 3530 students of both sexes from all the grades of 168 highschools applying multiple sampling methods included. All students completed sSchool Connection Questionnaire (SCQ) and Iranian Adolescents Risktaking Survey (IARS). The relation between tendency towards cigarrette, alcohol, drug use and 4 aspects of school connestion including belonging, commitment, engagement and relationship with peers investigated applying linear regression analysis.Findings: Engagement and commitment were more important in predicting risktaking than belonging and relationship with peers. Gender, family income, having alive father, having remarried parent, living with both parents and having failed to pass the last term successfully were predictive variables for tendency to abuse drugs mentioned here.Conclusions: School and its aspects had different effects on tendency to abuse drugs mentioned here.Relationship with peers in school had a positive effect on this tendency while commitment and engagement affected it reversly.