ABSTRACT This study examined a family therapy case of an adolescent with truancy to explore family dynamics associated with the adolescent’s development of truancy. The adolescent was a 14-year-old Korean male who had been truant for over a year in South Korea. His family involved in the therapy included the adolescent, his 45-year-old father, 44-year-old mother, 17-year-old sister, and 11-year-old younger brother. The parents sought therapy to address their son’s truancy issues. Using therapy logs and transcriptions, we employed a narrative case study to understand the family dynamics and therapeutic interventions. The identified characteristics of family dynamics were as follows: First, both parents had formed a negative internal working model and dysfunctional coping style due to their family-of-origin experiences. Second, the parents’ internal working model and coping style had a significant impact on the client’s development of his internal working model and coping patterns. Third, the client experienced unresolved emotions from the family at school, contributing to his truancy. The findings have implications for using the family systemic framework in addressing truancy, highlighting the interconnectedness of family dynamics and their impact on adolescent behavior.