This study proposed the democratic decentralization model as the decentralization model based on the reality of Korean society. The core of the “democratic decentralization” model starts with the question of who should respond to social risks. The social security policy was divided into four areas and divided into three levels in terms of sharing the roles of central and local governments. First of all, in the area of social security, the policy that national government should respond to social risks universally (national and universal), the policy that local governments should respond universally (local and universal), and the policy that the central government should respond selectively (national and selective) The policies were classified into regional and selective policies that local governments should respond to selectively. Korea s social security policy is not clearly divided in roles between the central government and local governments, and the criteria for role sharing are inconsistent. In this context, the “democratic decentralization” model is meaningful in that it provides a standard for who and how to respond to social risks in Korean society.