Objectives: The present study aimed to recognize the character and temperament dimensions of personality, the intermediate psychological risky and protective variables of drug use in boy adolescents, and to achieve a model for defining the types and rates of interactions between those aforesaid factors with the drug abuse itself on the other hand. Method: The sample included n=725 adolescent boys aged 16 to 18 years divided into three groups of adolescent those who had not used drugs , and those who had. The experiences of drug use, but stopped drug use in the year before, and finally those who were drug users Data were collected by filling in the short form of Temperament Character Inventory (T.C.I), Youth Self Report (Y.S.R) check list, drug use attitude questionnaire, and drug use questionnaire. The Amos-4 soft ware was applied for Structural Equation Modeling (S EM). Findings: Significant differences were found between the groups, given some qualities in their temperaments, characters, affective I behavioral and attitude problems. On the other side, the drug use model in adolescent boys contained fitness in the psychological level. Result: The results by Structural Equation Modeling indicated that measurement indices of the components have acceptable validity and reliability accordingly, based on these components, one can present a model in the psychological level as to define the drug use in adolescent boys