Since February 2022, the Ukrainian refugee crisis has been highlighting mental health problems associated with trauma and distress. This study aimed to evaluate the mental health status of twenty-seven refugee minors (10 to 18 years old) who fled Ukraine and temporarily settled in the Republic of Korea (ROK). This cross-sectional survey study aimed to evaluate the mental health status of ethnic Korean Ukrainian refugee minors. The Child and Adolescent Trauma Screen—Youth Report (CATS), generalized anxiety disorder seven-item scale (GAD-7), and subjective unit of distress scale (SUDs) were used for assessment. A preliminary analysis indicated that 77% Ukrainian refugee minors were exposed to and experienced war-related trauma. They are at a relatively low risk of trauma symptoms, anxiety, and distress due to stable family and visa status and a comparably better environment in the ROK. Meanwhile, refugee teenagers showed higher rates of psychological distress compared with refugee children. This finding suggests that an early psychological interventions in a host country may be beneficial to prevent mental health issues in refugee minors.