The purpose of this study is to provide Group Game Play Therapy Program to the Children in Elementary School and identify its effects on their self-regulation and peer relationships. For this purpose, Group Game Play Therapy Program was provided to 10 children in the experimental group who agreed to participate in Group Game Play Therapy Program once a week over eight weeks, and there were 9 children in the control group who didn't agree to participate. The collected data were processed by using SPSS 21 t-test, thus obtaining the following results: First, Group Game Play Therapy Program exerted significant effects on self-regulation among those children in the experimental group. Second, Group Game Play Therapy Program exerted significant effects on peer relationships among those children in the experimental group. To put the results together, Group Game Play Therapy Program was effective in improving self-regulation and peer relationships for the Children in Elementary School.