Recently，with the development of the pilot program of “an Appropriate Universal-type Child Welfare System”in China，the welfare provision and the realization of welfare rights in the vulnerable children has got great attention. However，at the same time，the welfare of urban vulnerable children remains grim as children’s welfare exclusion still exists， leading to the goal of the system unachieved. Taking four pilot cities in Jiangsu Province as an example and using an intersive interview，the article analyzes the problems in the operation of the system from the perspective of welfare exclusion. The study finds that the problem of the children welfare system is the welfare exclusion，which is mainly concentrated in two aspects of geographical and household identity. The fundamental reason of China’s vulnerable children’s welfare exclusion is the pattern of difference sequence in the field of welfare provision. Therefore，the most important way to get rid of welfare exclusion and reduce child welfare issues is to implement a unified standard as“Social identity”for children’s welfare provision and bridge the gap in different places.