The purpose of this study is to find which variable has the biggest effect on the school life adjustment of elementary school students among family strength, self-esteem, and the mother's rearing attitude. Second, the study observes how the elementary school student's self-esteem has a moderating effect regarding the rearing attitudes of their mothers and their school life adjustment. Five hundred forty-five fifth and sixth graders from an elementary school in Cheonan, are the participants of this study. The key research findings of this study are as follows: First, among the rearing attitudes of the mothers, family strength, and self-esteem, the variable that showed the greatest relationship with positive school life adjustment was family strength followed by self-esteem. Second, The self-esteem of the elementary school students showed a 1% moderating significant effect between the rearing attitudes of the mothers and school life adjustment. In the high self-esteem group of elementary school students, the moderating effect of self-esteem showed a higher level of school life adjustment when the students perceived that their mother had an affectionate rearing attitude, but showed a lower level of school life adjustment if they perceived their mother's rearing attitude as rejective or overprotective. Therefore, this study suggests that a focus on increasing self-esteem and family strength along with the affectionate rearing attitude of mothers is needed for the positive adjustment of elementary school students.