This study investigated the validity, reliability and factor structure of Adolescent Coping strategies (Frydenberg & Lewis, 1993 a) in Iranian adolescents. 799 high school students (365 males, 434 female) was selected through multi-stage sampling method and administered the ACS and Persian version of Defense Mechanism Questionnaire (Andrews, Singh, & Bond, 1993). The results based on item analysis (item-total correlation & difficulty degree) showed 12 items (correlated lowly with the total) constituted a sub-scale (apathetic withdrawal) whit alpha coefficient 0.63. Cronbach's alpha and test retest coefficient for the scale were 0.88 & 0.71 respectively. The result of principle component analysis (PC) and Promax rotation suggested the structure of the scale in Iranian population (deleting 5 items without the factor loads) contains 9 factors (help seeking, affiliation, worry, try & anticipation, focus of the positive, denial, passive aggression, seek spiritual support, physical recreation). Goodness-of-fit indices of confirmatory factor analysis confirmed the 9 extracted factors. In addition, the results of second-order factor analysis showed the model of two first order factors as adjusted (with 5 factors) and maladjusted (with 4 factors) strategies fitted more than the one-factor model. The positive correlation coefficients between the factors of ACS and Defense Mechanism Questionnaire confirmed the convergent validity of the scale.