Abstract:    As China has gradually entered the ranks of innovative countries, the scientific and technological innovation in China has undergone major changes, and the requirements for the construction of the national innovation system of China have also changed from improving the structure to improving the overall efficacy. The systematic characteristics of the national innovation system make the research and analysis of the national innovation system efficacy from the perspective of systems theory become the focus of scientific and technological innovation (STI) policy and management research. This paper attempts to introduce the system view, and on the basis of understanding the connotation of the national innovation system efficacy, systematically explore its generation mechanism and influencing factors, and deconstruct and analyze the national innovation system efficacy from the theoretical level. Firstly, based on the system characteristics of the national innovation system, this paper reveals the connotation of the national innovation system efficacy from the perspective of "system structure - system operation - system function", understands it as the organic integration of the result performance and process performance, and analyzes the generation mechanism and interaction of the two kinds of performances respectively. Secondly, integrating the multi-dimensional perspectives of "system structure - system function", "system input - system output", and "system internal operation - system external opening", this paper constructs the system analysis framework of the factors affecting the national innovation system efficacy and the constructs the system structure and general system operation mode of the national innovation system from the perspective of the sub-system efficacy under the function orientation of S&T research and industrial innovation, pointing out that systemic thinking is needed to enhance the efficacy of national innovation system. On this basis, the paper proposes the suggestions of systematically promoting the efficacy of the national innovation system in three dimensions, which echoes the need for high-quality transformation of the China′s national innovation system: optimizing the system structure and layout to improve the result performance of the national innovation system, promoting the multi-level circulation of innovation elements to improve the process performance of the national innovation system, and organically integrating the innovation environment to realize the overall efficacy improvement of the national innovation system. In addition, this paper also proposes four future research directions for deepening the systematic understanding of the national innovation system and promoting the efficacy improvement of the national innovation system. Overall, this study has certain theoretical and policy contributions. In theory, this study is a theoretical exploration of the systematic deconstruction of the national innovation system efficacy. Through the analysis of the system generation mechanism and influencing factors of the national innovation system efficacy, it lays a theoretical foundation for the research of the national innovation system efficacy and broadens its analysis methods. In terms of policy, this study provides some reference for the government to further improve the construction of the national innovation system and enhance the national innovation system efficacy. This paper constructs an analysis framework of the factors affecting the national innovation system efficacy and proposes a systematic way to improve the national innovation system efficacy, which helps guide policy makers to systematically consider the policy integrity in the process of formulating and implementing policies, and fully consider the synergy between system structure, system operation and system environment in the design of the governance mechanism of the national innovation system.

Key words: national innovation system, efficacy analysis, systems theory, generation mechanism, influencing factor