Abstract: A high-level socialist market economy system is mainly embodied in the specific institutional framework of “two unshakable ownership bases + a large national market + a dynamic government + a new distribution mechanism + a high level of open economy”. It is the main task of economic transformation and development to reform the framework and connotation of this system in the process of realizing Chinese-style modernization. Since the 18th National Congress, some obvious structural institutional problems have emerged in China’s economic operation, such as ambiguity in the definition of market-oriented reform areas, market segmentation, and asymmetry in internal and external openness. In the process of building a high-level socialist market economy system, we must face the challenges from major influencing factors at home and abroad, such as the restructuring of the global industrial chain, the formation of a dominant domestic market pattern, the transformation of industrial policy, and the adjustment of income distribution, and be well prepared in terms of strategies and policies.