Using questionnaire data from a sample of 1,139 adolescents, this study examines gender differences in causes of delinquent behavior. First of all, the results show that boys who have internalized patriarchal characteristics are more likely to commit deviant behaviors. Many studies have revealed that girls who internalize the traditional symbolism regarding sex are less likely to commit deviant behavior. However, the effect of patriarchy had been uncertain in boys. Second, this study also found that girls who are raised in egalitarian households are more likely to commit deviant behavior compared to girls who belong to traditional patriarchal households. These results support that traditional patriarchal power differently affects adolescent delinquency in terms of gender difference. Both in boys and girls, this study found no association between parental controls and deviant behavior regardless of type of parental control whether it is instrumental or relational. However, boys who have bad a relationship with their fathers are more likely to commit delinquent behaviors, even when other variables are controlled. This finding indicates that children's negative relationship with their parents can be a much stronger cause of delinquency, compared to a positive relationship with parents, which can be a suppressor of delinquency. Third, recognition of punishment has a significant relationship with delinquency while its gender differences were not found. Fourth, patriarchal characteristics do not affect adolescents' group risk and recognition of punishment. However, considering association with delinquent friends, boys who have more patriarchal characteristics are more likely to be involved with delinquent friends. Therefore, patriarchal characteristics of boys not only increase the chance of delinquent behaviors, but also affect their association with delinquent peers. For girls, however, patriarchal family structure is a significant cause of association with delinquent friends. This finding implies that involvement with delinquent friends for girls plays a role of exit to escape from the pressure of patriarchal control in traditional patriarchal families. This study suggests that patriarchy should be considered carefully in terms of gender difference to explain adolescent delinquency, including important factors in criminological work.