This study discusses the feature and effect of colors and explores the possibilities of the use of colors in the clinical area. The efficacy of color psychology and its application had been examined through total 82 precedent studies published by academic journal from 2000 to 2010. Consequently, it is appears that color psychology and its use could help understand deep emotional sense of children, and work effectively on development of self-expression. The result shows that colors represent various changes of human’s mentality and emotion in clinic. And the program using colors helps the clients express their emotion, relax the tension and gain psychological stabilities. In addition to this, because the selection and use of colors vary depending on symptoms, colors are important factors as assessment and diagnostic tool.