The purpose of this study is to investigate the impact of an activity-oriented group art therapy program based on care theory on the self-concept of school-aged children from underprivileged classes. The subjects of the study were eight students from underprivileged classes attending B Regional Children's Center in City A who had difficulties due to unstable behavior and were recommended by the center director. The activity-oriented group art therapy based on care theory was conducted with a total of 10 sessions, 1 to 2 times a week, 90 minutes each. The self-concept test was conducted before and after the program to verify effectiveness. For statistical processing, SPSS 23.0 was used to compare and analyze changes between pre- and post-tests using a paired-samples t test. Additionally, an assistant observer videotaped the entire process and described the content. To summarize the results, first, activity-centered group art therapy based on care theory was effective in improving the self-concept of underprivileged school-aged children. Second, the activity-centered group art therapy program based on care theory improves behavioral adaptability, intellectual ability and school status, physical appearance and characteristics, freedom from anxiety, popularity, and changes in happiness/satisfaction among the sub-factors of self-concept of underprivileged school-aged children, and which shown to be effective. The results show that activity-oriented group art therapy based on care theory had a positive effect on the self-concept of underprivileged school-aged children. Therefore, the activity-centered group art therapy program based on the care theory of this study presented basic clinical data for improving the self-concept of underprivileged school-aged children.