Relationship Enhancement Parent Effectiveness Training(REPET) is a parent education program to improve parent-child interpersonal relationship to heal the intellectual and emotional problems of teenagers. The purpose of this study was to apply PET in an effort to examine its effects on the communication of parents with children, their parenting attitude and children\'s self-esteem. The subjects in this study were 50 mothers whose fifth-grade children attended C elementary school in the city of Busan. An experimental group and a control group were made up of 25 children each. The instruments used in this study were Sin Doo-kyun(1988)\'s Parent-Child Communication Inventory, Lee Won-young(1983)\'s Parenting Attitude Inventory and Choi Hyeon-rim & Lee Hyeon-joo(2003)\'s Self-Esteem Inventory. An experiment was implemented, and a pretest and posttest were conducted before and after that respectively. Kim In-ja\'s Korean version of PET(1989) was applied in eight sessions, and ANCOVA was employed to make a statistical analysis of the collected data. The findings of the study were as follows; First, REPET was effective at boosting parent-child communication. Therefore the parent education program that focuses on improving parent-child interpersonal relationship could be applied when there is a necessity to enhance parent-child communication. Second, REPET had a good effect on changing all the four kinds of parenting attitude into the right direction, which included affectionate, rejective, autonomous and controlling styles. Accordingly, the parent education program could be applied when parents need to get training in parent role performance to raise their children well in consideration of their characteristics. Third, REPET was effective at boosting the self-esteem of children as well. It indicated that the parent education program could bring an ideal change to children\'s affective characteristics by bolstering parent effectiveness, and that program could be applied in a diverse way to iron out parent-child problems. Key Words: PET, communication skills, the parenting attitude of parents, children\'s self-esteem.