This paper traces the evolution of the concept and its content of "new infrastructure construction", which is highly concerned by the all since it was put forward by the decision maker. Based on the investigation and analysis of the close connection between theory and practice, the paper clarified that the new infrastructure construction is not only an important measure to support the "Fighting the COVID-19 Disease" and to expand domestic demand in China, but also a major event to help build a "New Economy" , create high-quality development momentum and stride over the "Middle Income Trap". While there is a lot of room to do it in China, subjective efforts must be closely combined it with reform and mechanism innovation, making a integrated development with “institutional infrastructure” . In particular, this paper points out that private enterprises’ role and PPP mechanism innovation in the new infrastructure construction should be paid special attention; For the digital platform companies which are closely related to the new infrastructure, we need to make a rational analysis and clarification with the times to deepen understanding of its economic and social value.; In connection with the new infrastructure construction, local governments must persist in market orianted reform and creat spicific innovational measures in the jurisdiction of the supply-side structural reform, to seek the high-level customized solutions.