This study intends to grasp the structural relation between children's mother attachment, self-esteem, quality of peer relationship, and maladjustment behavior, and then to investigate mediating effects of self-esteem and quality of peer relationship from the relationship between a child's mother attachment and maladjustment behavior. The study investigated 769 children who are in the 5th and 6th grade of 6 primary schools. Results of the study are summarized as follows. Self-esteem and quality of peer relationship plays a complete medium role in mother attachment and maladjustment behavior, which is deemed that attachment has indirect influence over maladjustment behavior through self-esteem and quality of peer relationship rather than having direct influence over maladjustment behavior. This study has a meaning to provide information so as to prevent maladjustment behavior of a child and to make them adapt better to their surroundings by utilizing internal and external resources of a children.