This study aimed to find out 1) the differences in deviant behavior tendencies of middle and high school students according to demographic variables, 2) the relationships between their deviant behavior tendencies and psycho-social intervening variables, and 3) the effect of psycho-social variables on the disobedience to social norms. Participants were 1,586 students in Seoul and Incheon city. The subjects consisted of 383 middle school students(256 male and 127 female) and 1,203 high school students(545 male and 658 female). The data were collected by the following tools: Home Atmosphere Diagnostic Scale standardized by Young-joo Ryu(1986), which was originally developed by Roach(l975), Social Norm Observance Scale and Scale for Reaction to Punitive Sanction against Deviant Behavior developed by Sungtak Im(2001), Inferiority Scale by Yong-man Kim(l995), and Self-Efficacy Scale by Yong-shin Park(1997, 2000). The collected data were andlyzed emplying Pearson's product-moment correlation analysis, t-test, one-way ANOVA, and stepwise multiple regression analysis by SPSS 10.0. The findings of this study were as follows: First, male students tended to disobey more social norms than female students. While male students were more deviant from sex-related social norm and general violence, female students were more from public morals. Second, the more home atmosphere were positive, the less the possibilities of deviant behavior. Third, middle school students' deviant behavior tendencies were significantly affected by their inferiority, while the deviant behavior of high school students were affected by home atmosphere, self-efficacy and inferiority. Fourth, high school students' deviant behavior from public norms were more serious than middle school students; and female students were more serious than male students as well. Fifth, it was found that male students; violence related to their home atmosphere and self-efficacy. The students being of more deviant behavior were characterized by more positive home atmosphere, higher assertion efficacy and social efficacy, and lower relational and parental efficacy. Sixth, high school violence were generally more serious than middle school. Finally, students having father with lower educational level had higher possibilities of deviant behaviors.