This study was conducted to find out the impact of group art therapy on self-expression and sociality of children in the senior grade (5th to 6th grade) of the local children s center elementary school. To this end, eight senior children from a local children s center elementary school in A-si participated in the experiment, and eight senior children from a nearby local children s center elementary school were analyzed as a treatment-free comparison group. A total of 12 group art therapy programs were conducted once a week for 80 minutes to the experimental group, and the effects of the program were measured in advance. The measurement tools used a self-expression ability scale and social skills test, and a projective picture test KSD was conducted to measure changes in school life. The results of the study are as follows: First, group art therapy programs have been shown to have statistically significant effects on both spoken, spoken and verbal representations, which are sub-regions of children s self-expression. Second, group art therapy programs were found to have significantly influenced both diligence, responsibility, cooperation, compliance, and self-reliance, which are sub-regions of children s sociality. Third, the children s school life test also shows a lot of activities together in post-mortem tests, indicating that children s social skills have improved. These results show that group activity-oriented group art therapy has a positive impact on the self-expression and sociality of children using local children s centers.