This study investigates how the music activities based on positive psychology affect the self-esteem and preparation for self subsistence of youths in institutional care. For this purpose, 24 youths in care were randomly divided into two groups-an experimental group of 12 adolescents and a control group of 12 adolescents. The positive psychology-based music activities program took place twice a week from January 15 to February 23, 2019, totaling 12 sessions with 50 minutues, respeictively. The results of this study are as follows. First, the experimental group that participated in the music activities program based on positive psychology showed a significant improvement in terms of self-esteem, compared to the control group. Second, the experimental group also improved significantly in self-reliance preparation, compared to the control group. Furthermore, the experimental group showed a significant difference from the control group with regard to independent-mindedness, interpersonal skills, and problem-solving skills, which are sub-sectors of self-reliance preparation. This suggests that the positive psychology-based music activities can be an effective intervention for improving self-esteem and self-reliance preparation of youths in institutional care.