Born in Pyongyang in 1914, Choe Ung-sok was a physician who lived through the Japanese colonial era (1910-1945), rule by the United States Army Military Government in Korea (USAMGIK; 1945-1948), and national division (1948). Influenced by socialism and social hygiene/social medicine during his studies in Japan, he played the role of representing the socialist camp in the discussions related to the construction of a heath care system immediately following the Liberation (1945). His key arguments were: first, the nationalization of the medical system and the implementation of nationwide programs to eradicate diseases; second, the provision of free medical services through the expansion of social insurance; third, the reeducation of the medical personnel; fourth, the provision of social sciences education to the medical personnel and the reorganization of medicine into preventive medicine; fifth, the nationalization of pharmaceutics; sixth, the laborers’ establishment of autonomous medical organs (affordable clinics, medical consumers’ unions through cooperatives); and seventh ,the reduction of work hours to 6-8 hours, technical improvement, respite from research, and guarantee of economic life for the medical personnel. Influenced by the medical systems of the Soviet Union and Japan, such arguments stood in opposition to the right wing’s plan for the construction of a relatively passive health care system at the time but, in the end, failed to be realized in southern part of Korea under the USAMGIK. Subsequently, he defected to northern part of Korea and came to participate in the task of constructing North Korea’s health care system. Choe’s life and design for a health care system provide examples through which one can confirm the nature of social hygiene/social medicine both during the Japanese colonial era and before and after the Liberation and the contents of the design related to a health care system as held by the socialist faction. In addition, they show that, immediately after the Liberation, there existed a broad spectrum of imagination and arguments concerning the desirable health care system. Following the division of the Korean Peninsula, South Korea witnessed the instatement of a regime that established anti-communism as the state policy and the strong influence of the United States in politics, economy, and culture. The consequent frustration of Choe’s design for a health care system and his defection to North Korea frustrated the creation of a National Heath Service (NHS) in South Korea, reinforced the tendency to view NHS and social insurance as “socialist” or “communist” methods, and led to the restriction of the scope of subsequent discussions related to health care system. In conclusion, the course of Choe’s life and thought went beyond the life of an individual during a period in which diverse ideologies collided through the Japanese colonial era, Liberation, and national division and symbolically demonstrates one important path of the process of constructing a health care system on the Korean Peninsula.