The study aimed to examine the effects of group art therapy based on reality therapy on the daily stress, internal-external control, and self-efficacy of children. The subjects of this study were 4th to 6th grade of elementary school students who were referred by K elementary school teachers, in H city. Ten children who received parental consent participated. From September to December 2018, group art therapy was delivered based on reality therapy of 16 sessions, 60 to 90 minutes each once a week. The Daily Hassles Questionnaire for Children (DHQ-C), Internal-External Control Scale (IECS), and Self-efficacy Scale (SES) were used to assess changes in the pre- and post-test. Data analysis was also performed using the SPSS program, and results were analyzed by quantitative and qualitative analysis. Group art therapy based on reality therapy showed a statistically significant effect on the daily stress of children. Also, group art therapy based on reality therapy demonstrated a statistically significant effect on internal-external control of children. Furthermore, art therapy based on reality therapy showed a statistically significant effect on self-efficacy. Future research is needed to engage both children and their family to gain a deeper insight.