Children protection is a consensus in the civilized society. Under the influence of improving the classification of children’s security system and “Outline for Chinese Children Development（2011-2020）” in Third Plenary Session of the Eighteenth Conference of CPC，the plight children are paid greater attention. The increasing news reports，academy study and social service related to plight children shows that the plight children hare already become a social problem which grasps the universal attention from the government and society. This article starts from the actual problems of plight children，and goes deeper to the areas of specific category，living condition，security requirement，responsible main body. Meanwhile，we explore and analyze the way to make these things happen. The purpose of the article is to push forward the social security system of moderately universal type of plight children in China.