The purpose of this study was to verify the effect of re-creative instrumental playing on self-encouragement and emotional expression in school-aged children. The participants in the study included a total of 433 students from 16 classes(grades 1~6) in 7 school under the Seoul ○○ Office of Education, and 9 classes(grades 1~6) in 7 school under the Chungnam ○○ Office of Education. Ultimately, data from 409 participants were used for analysis. Re-creative instrumental playing was conducted from October 19 to December 6, 2023, involving the entire student of each class in the schools, with sessions held 2~4 times. To measure the level of self-encouragement and emotional expression in the research subjects, the Child Self-Encouragement Scale and the Korean Child Emotional Expression Scale were utilized. The data were analyzed using SPSS version 26.0 with paired t-test. The results indicated statistically significant differences in emotional self-encouragement(sense of self-inspiration, self esteem) and emotional expression(difficulty in emotional awareness, difficulty in emotional expression) of school-aged children before and after participating in re-creative instrumental playing. This study holds significance in confirming the effectiveness of re-creative instrumental playing, a method within music therapy, in promoting selfencouragement and emotional expression in school-aged children.