In the era of globalization and postindustrial economy, many countries are changing or reconstructing their welfare systems to varying degrees in response to the economic development and social changes. On the basis of analyzing the influence of new social risks on the construction of moderately beneficial social welfare system in the era of globalization and postindustrial economy, the article puts forward that China should reconstruct the social foundations of the construction and development of welfare system from the following three aspects: firstly, to establish and develop the model of shared responsibility of the new welfare system; secondly, to establish the triangle relations of welfare among the state, non-profit sector and family by means of risk management; thirdly, to establish and develop the protection mechanism of citizenship under the new social contract.