The purpose of this study is to examine whether the mediated effect of college students self-concept clarity mediated the effects of parental psychological control perceived by college students on their relational aggression. The sample of the study was 250 students (male:;121, female:;129) from colleges located in Seoul, Gyeong-gi, Gangwon-do, and the Gyeongsang-do area. Psychological Control Scale-Youth Self-Report (PCS-YSR), Self-Report of Aggression and Social Behavior Measure (SRASBM), Self-Concept Clarity Scale (SCCS) werewas used, and SPSS 22.0 program was utilized for the data. The results of this study are summed up as follows: First, Tthere was no gender difference in the mother s psychological control, self-concept clarity, and relational aggression perceived by college students. Secondly, Tthe mother s psychological control perceived by college students showed a positive correlation with relational aggression and a negative correlation with self-concept clarity. Self-concept clarity and relational aggression showed a negative correlation. Thirdly, Tthe mother s psychological control perceived by college students had a direct influence on relational aggression. In additionFourth, it was found that self-concept clarity partially mediated the effect of the mother s psychological control perceived by college students on relational aggression. Through these research results, it was confirmed that the psychological control of the mother perceived by college students affects relational aggression through self-concept clarity. Based on this, when consulting college student clients, it is necessary to intervene in a way that increases the clarity of college students self-concepts instead of the psychological control of mothers who have difficulty in direct access. In addition, it is hoped that relational aggression can be lowered to help college students have smooth interpersonal relationships and adaptive college life.