The purpose of this study was to examine if stability of self-esteem mediated the relation between self-discrepancy and interpersonal satisfaction. Three-hundred-and-fifty-nine middle and high school students were recruited and asked to complete measures of self-discrepancy, interpersonal satisfaction, and stability of self-esteem. The mediation effects were examined using the method raised by Baron and Kenny (1986). The results indicated that adolescent self-discrepancy between actual and ideal self-concept were negatively correlated with interpersonal satisfaction and stability of self-esteem and interpersonal satisfaction and stability of self-esteem were positively correlated. The results further indicated that the relation between self-discrepancy and interpersonal satisfaction were partially mediated by stability of self-esteem, implying that discrepancy between their actual and ideal self-concept could contribute negatively to adolescents’ satisfaction with interpersonal relationships directly and indirectly by lowering their stability of self-esteem as well. Lastly, clinical implications of these findings were discussed and recommendations for future study were made.