Objectives : This study investigated the influence of traumatic experience on the ego identity, self-esteem, and general psychopathology of adolescent North Korean refugees. Methods : The participants were 146 adolescents North Korean refugees who attended H High School for North Korean refugees. We divided the subjects into two groups according to the severity of their traumatic experience : the more-traumatic-experience group and the less-traumatic-experience group. Each group performed self-report assessments including an assessment to reveal demographic characteristics, the Traumatic Experiences Scale for North Korean Defectors, the Scale for Ego identity, the Scale for Self-esteem and the Symptom Check-90-Revision (SCL-90-R). Statistical analysis of t-test and multiple regression utilized SPSS 12.0 for Window for comparison between more-traumatic-experience group and less-traumatic-experience group. Results : The prevalence of posttraumatic stress disorder among adolescents North Korean refugees was 37%. The factor with the greatest influence on ego identity was length of time living in South Korea, while, for self-esteem the most influential factor was perception of health. The more-traumatic-experience group had lower self-esteem scores on some subscales of the Scale for Ego identity. They had higher scores on all SCL-90-R subscales than the less-traumatic-experience group. Conclusion : Adolescent North Korean refugees experienced high rates of posttraumatic stress disorder. The more traumatic-experience-group had lower self esteem and poorer ego identity and mental health than the less-traumatic-experience group.