Advancing the construction of the national innovation system is of great significance for supporting the realization of Chinese modernization through the modernization of science and technology By conducting an indepth analysis of the conceptual connotation of the national innovation system, this paper proposes an analytical framework of “Mission OrientationInnovation ActivitiesSystem Composition” It systematically reviews the evolutionary development of China’s innovation system, arguing that it has undergone four stages: selfreliance, marketoriented transformation, independent innovation, and innovationdriven development This evolution demonstrates a shift from improving the system’s composition to enhancing the level of innovation activities The paper delves into the major situational changes and existing shortcomings facing China’s innovation system It proposes the theoretical logic for advancing the construction of the national innovation system in the new era: coalescing efforts through the strategic goal of building a scientific and technological powerhouse, strengthen the applicationoriented approach to enhance the integration level of innovation activities, and consolidating the foundation for efficacy improvement by perfecting the system composition In practice, advancing the construction of the national innovation system requires adherence to systems thinking and a problemoriented approach, using several landmark measures as levers to lead a leap in the overall efficacy of the national innovation system