The purpose of this study was to find out a change of depression`s level in a course of time and predictors of depression of North Korean defectors in South Korea. This survey was conducted on 200 North Korean defectors with questions on depression, psychological trauma in North Korea and escape process from North Korea in 2001. Among them, 151 North Korean defectors were followed up with questions on depression, stress experience in South Korea and socio-demographic characteristics in 2004. Result indicated that depression of North Korean defectors was significantly increased during three years, and especially depression of men was significantly increased. The level of depression of an old age group, a marriage experienced group in North Korean, a poor health group, and a chronic disease group was higher than any others. In 2001, no graduation from University in North Korea and less psychological trauma in North Korea predicted depression of North Korean defectors. In 2004, marriage in North Korea, more psychological trauma in North Korea, less psychological trauma in escape process from North Korea, and more stress in South Korea predicted depression of North Korean defectors. Finally, adjustment, therapeutic interventions, mental health service programs of North Korean defectors and further study were discussed.