The support system for the extremely poor is a social security system with Chinese characteristics that has been in existence since the founding of the People's Republic of China and has been constantly developing and improving. With the continuous improvement of the social security system, the integration of urban and rural social security has made important progress in improving the fairness of people's livelihood security, but there is still a problem of unbalanced and inadequate development in the security gap between urban and rural areas and regions with different economic development levels. Through the investigation and analysis of the policy and practice of the special support system in Jiangsu Province, this paper understands the operating status, results and problems of the special support system, and draws on the international experience of the relief system and implementation of the special support system to provide reference for the construction and improvement of the special support system in China.