The purpose of the study was to examine the effects of psychomotoric play therapy program on reducing stress and improving social self-efficacy of children. The subjects of the study were divided into the experiment group of 12(8 boys and 4 girls) and the control group of 12 children(1st~3th gr) in Y elementary school. Before and after the program, stress level and social self-efficacy were tested in both groups by questionnaires. The gathered data were statistically analyzed by Wilcoxon test, Mann-Whitney U test and a researcher investigate the qualitative materials. The results of this study were as follows: First, the psychomotoric play therapy program was effective on reducing stress such as school and peer relationship stress of school children. Second, the psychomotoric play therapy program was effective on improving social self-efficacy of children.