The purpose of this study was to examine the relationship between maternal overprotection and children's ego-resilience & school life adjustment and then verify whether or not children’s ego-resilience played a mediating role in the relationship between maternal overprotection and school life adjustment. For this, a questionnaire survey of elementary school fourth-fifth-and sixth-year students in their 10-12 years of age in Gyeonggi-do was carried out. The data of 501 responses were used in study analysis, except the data of insincere or incomplete responses. Study findings are as follows: First, maternal overprotection had negative correlations with children's school life adjustment. In addition, maternal overprotection had negative correlations with children's ego-resilience. On the other hand, children’s ego-resilience had positive correlations with school life adjustment. Second, in order to look into whether or not children’s ego-resilience plays the role of mediating effect in the relationship between maternal overprotection and school life adjustment, structural equation model verification was carried out. Results showed that children's ego-resilience had a partial mediating effect. So far, overprotection has been studied only as a sub-variable of child-rearing attitudes, but in recent times, studies that mainly dealing with overprotection are carried out. However, studies that deal with the relationship between maternal overprotection and children’s ego-resilience & school life adjustment comprehensively are rare for the present. In this regard, this study seems to be meaningful in that it examined maternal overprotection and children’s ego-resilience and school life adjustment comprehensively, and study findings will be basic data for parental education and school education.