본 연구는 북한과 탈북과정에서 경험하였던 북한이탈주민의 외상사건이 이들의 남한사회 적응에 미치는 영향을 탐구하였다. 또한 이러한 외상사건의 경험에 의한 부정적인 요인이 심리적으로 어떻게 발현될지에 관심을 가지고 복합 외상후 스트레스장애에 주목하였다. 이에 본 연구는 북한이탈주민의 외상경험과 그들의 남한사회 적응의 관계에 있어 복합 외상후 스트레스장애가 매개효과를 나타내는지 검증하였다. 이를 위해 서울과 경기 지역에 거주하는 북한이탈주민을 대상으로 설문을 실시하였고 405명의 자료를 수집하여 분석하였다. 주요 결과는 다음과 같다. 첫째, 독립변수인 북한이탈주민의 외상사건 경험이 매개변수인 복합 외상후 스트레스장애에 부정적인 영향을 미치는 것으로 나타났다. 둘째, 독립변수인 북한이탈주민의 외상사건 경험이 종속변수인 사회적응에 부정적인 영향을 미치는 것으로 확인되었다. 셋째, 북한이탈주민의 외상사건 경험과 사회적응의 관계에 매개변수인 복합 외상후 스트레스장애가 투입되자 외상경험과 사회적응의 유의미한 관계가 사라지고 매개변수인 복합 외상후 스트레스장애만이 사회적응에 통계적으로 유의미한 영향을 미치는 것으로 나타났다. 이로써 북한이탈주민의 외상사건 경험과 남한사회 적응의 관계에서 복합 외상후 스트레스장애의 매개효과는 완전 매개효과로 확인되었다. 이러한 결과를 바탕으로 북한이탈주민의 사회적응을 촉진할 수 있는 개입 방안을 제시하였다. The purpose of this study is to examine the impact of the traumatic incidents of North Korean refugees in North Korea and during the process of defection on their adaptation to South Korean society. And their complex post-traumatic stress disorder was selected as a noteworthy variable, as this study focused on how negative factors caused by their experience of traumatic incidents were manifested psychologically, and whether the complex post-traumatic stress disorder of North Korean refugees had any mediating effect on the relationship between their trauma experience and adaptation to South Korean society was analyzed. After a survey was conducted on the North Korean refugees who resided in Seoul and Gyeonggi Province, the collected data from 405 respondents were analyzed. The major findings of the study were as follows: First, the North Korean refugees' experience of traumatic incidents that was the independent variable was found to have exercised a negative influence on their complex post-traumatic stress disorder that was the mediator. Second, their experience of traumatic incidents was found to have exerted a negative influence on their social adaptation that was the dependent variable. Third, when their complex post-traumatic stress disorder was inputted in the relationship between experience of traumatic incidents and social adaptation, there was no more significant relationship between experience of traumatic incidents and social adaptation, and only complex post-traumatic stress disorder was found to have affected social adaptation significantly. Thus, it's found that the complex post-traumatic stress disorder of the North Korean refugees had a full mediating effect on the relationship between their experience of traumatic incidents and adaptation to South Korean society. Given the findings of the study, the kind of intervention that could facilitate the social adaptation of North Korean refugees was suggested.