PPP has become an important tool for the supply of public goods and services，and it is also a hot spot in academic researches. Based on the Bibliometric，this paper divides the theoretical research of PPP in China into three stages：exploration，development and transformation. The results show that the theoretical connotation of PPP research has undergone evolution in transaction mechanism，management and motivation：from BOT to PPP in a more broad sense for the mechanism. The management extends from project level to contract level，and public management has been applied. The motivation of transaction has transformed from the “introduction” of foreign capital to the “going global” of Chinese enterprises in the context of the the Belt and Road Cooperation. This report provides a reference for future PPP research and guidance for the practice of PPP projects and market development in China.