This study aims to understand Korea's social security policy draw its implications for future developments. This study out- lines the history of social security in Korea over the past 100 years, and also summarizes the development of various social security programs. In addition, the development process of so- Cial security was systematically discussed in connection with citizenship and social rights. The development of industrialization and democracy helped establish rights to social security based on citizenship and so- Cial rights. In addition, globalization has led to international agreements on efforts to guarantee the social rights of the vulnerable. Social security in Korea over the past 100 years has devel- oped in the following way. First, in the colonial era, social proj- ects were carried out in Korea with the purpose of serving the Japanese rule in Korea. However, those social projects did not develop in the direction of ultimately solving the social problems of Joseon. However, since it was aimed at governance, various social projects were carried out through a clear com- munication system, which has contributed to laying the admin- istrative foundation of social policy after independence. Second, the period spanning from the national independence to the 1960s was characterized by the beginning of the capital- ist distribution system and the aid welfare system. The 1960s and 1970s were characterized by industrialization and partial introduction of social security. In particular, major social se- curity systems for pension insurance, medical insurance, in- dustrial accident insurance, and public assistance were legis- lated during this period. Third, the years 1980-1997 were char- acterized as a period when social security was expanded as the dictatorship collapsed and the democratic system began. Along with the increasing demands of the people, the welfare ministry and the delivery system were substantially strengthened. Fourth, finally, from the 1997 financial crisis to the present, it is characterized as an era of a full-fledged welfare state. Along with the expansion of public assistance, social security systems related to caring to cope with the aging population and low birthrate were strengthened, and the universality of the welfare system was strengthened. The components of Korea's social security system have de- veloped through various processes. First, in the case of health insurance, in 1989, 12 years after it was applied to workplaces with 500 or more employees in 1977, the coverage was ex- tended to include even self-employed persons. The challenge facing the National Health Insurance is to ensure its sustain- ability by improving the efficiency of health care delivery along with the continuous reinforcement of the system system. Second, the national pension has expanded its subscribers to all citizens 10 years after its introduction in 1988. Currently, ef- forts are needed to find the optimal point between reinforce- ment of retirement income security and guarantee of financial stability. Third, industrial accident insurance was introduced in 1964 and employment insurance was introduced in 1995. At present, efforts are needed to reduce widespread blind spots and strengthen the security. Fourth, childcare and early child- hood education have developed rapidly since the early 2000s. Currently, there is a conflict between the universality and se- lectivity of the institution, but in the long run, it is necessary to move toward strengthening the universality. Fifth, due to the rapid aging of the population, the elderly care service policy has developed rapidly since the 2000s. Although the quantita- tive expansion of the system has been achieved, there is a need for considerations to efficiently provide quality services now. Sixth, social security for the disabled was dominated by an ac- ceptance-oriented policy, but policies for the disabled have developed in earnest since 2000. The social security policy for the disabled faces the challenges of strengthening the support system in order to strengthen the social integration of the disabled. Seventh, in order to effectively deliver such policies, the social welfare delivery system has been continuously developed. In particular, the provision of customized services centered on consumers is being implemented through the in- formatization project and the maintenance of the local govern- ment welfare administration system.