The policy design and implementation processes for vulnerable populations in disasters are scattered across various governmental agencies in Korea including the Ministry of Gender Equality and Family, the Ministry of Health and Welfare and the Ministry of Public Administration and Security, depending on the type of the vulnerable and the nature of the disaster. Moreover, there is no effective strategy to assist the vulnerable during the processes of disaster response and recovery. Therefore, this study aims to improve the support system for the victims of disasters in Korea by analyzing and comparing the U.S. and Japanese systems of protecting and supporting the vulnerable. Based on the lessons from the two countries, we analyze the current status of disaster support system in Korea and draw implications for policymakers and practitioners in Korea. In conclusion, the study suggests several measures to improve the support system for the vulnerable in Korea, including legal reform, organizational reconstruction, and clear identification of tasks and responsibilities among relevant government agencies.