South Korea is changing into a multi-cultural society, due to an increase in international marriage, foreign workers and transcultural immigration. In addition, the number of North Korean defectors entering South Korea has increased and now, there are approximately 25000. Therefore, this review have focused on a research that pertains to adaptation and mental health concerns of their children. Children who have immigrated themselves or whose parents have immigrated, might experience language barriers, difficulties in school adjustment, identity confusion and mental health problems. However, their academic performance and developmental status are known to be variable and be affected by socioeconomic status and their parents' educational level. Studies that evaluated the psychological problems of North Korean adolescent refugees' indicated the need for interests in both emotional and behavioral problems. The risk factors of North Korean adolescent refugees' mental health are suggested to be past traumatic experiences, long duration of defection and short period of adaptation. When mental health professionals provide assessment and treatment, they should consider the pre- and post-migration experiences & cultural background that affect the illness behaviors and attitudes toward mental illnesses. Lastly, the majority of children with multi-cultural background are still under an adolescent period and we should follow up with long-term perspectives.