This research was performed to investigate the effectiveness of self-esteem promotion program(SEPP) to adolescents with minor delinquency on self-esteem and mental health. Samples of this study were 36 adolescents with signs of minor delinquency in the third grade of middle schools who reside in K city. Data analysis was conducted by chi-square test which tests the general homogeneity between the experiment group and the control group. To test hypothesis how SEPP affects on self-esteem, mental health, and delinquency, paired t-test was performed. The results were summarized as follow; 1. After the experimental treatment, self-esteem score was not statistically significant. 2. After the experimental treatment, mental health score was statistically significant. 3. After the experimental treatment, self reported delinquency score was statistically significant. As the result of this research, the SEPP increased the degree of mental health and decreased that of delinquency of the adolescents who committed minor delinquency. Self-esteem is difficult to be changed by itself in number for a short time, but there is potential effect, which can be expected the preceding changes of mental health and behavior of participants.