Objective: The present study was designed for prediction of adolescents risk behaviors on the basis of positive & negative mental health. For this purpose 6 domains of risk behaviors were studied: violence, suicide, cigarette smoking, alcohol use, substance abuse and unsafe sexual relationship. Method: Subjects were included 385 adolescents (197 girls & 188 boys) 14 -16years old that were students in grade one to three of high schools in region 5 of Tehran in 83-84 educational year. In order to collect the data, demographic characteristic questionnaire, GHQ-28, psychological well-being scale (p.w.s) and risk behaviors checklist were used. Findings: The findings indicate that there is significant difference in most of positive and negative mental health indicators between adolescents with risk behaviors and those haven’t. Result: The results of this research demonstrated that both of positive and negative mental health's involve in incidence of adolescent risk behaviors. Therefore both of dimensions of mental health should be paid attention for designing of preventive interventions.