The purpose of this study was to develop an instrument for measuring self-concept for children and adolescents in a self-evaluation form. Methods: The participants consisted of elementary and middle school students selected from five schools in urban areas (n=2,407). The scale developmental processes included construction of a conceptual framework, development of preliminary items, verification of content validity and reliability, and concurrent validity of final items. Results: There were no items deleting and resulting 80 final items including 4 subscales: Physical self-concept (20 items); Emotional self-concept (20); Social self-concept (20); and Academic self-concept (20). The internal consistency was acceptable (Cronbach``s ?=.97). The scale classification provides a description of self-concept degree from very positive to very negative. In this study, self- concept was significantly correlated with depression (-0.77≤r≤-0.51, p<.001). Conclusion: The results of this study will be useful not only for measuring self-concept of Korean children and adolescents but also for understanding their self-concept development. However, repeated research is needed for further validity and reliability tests of this measurement tool.