Abstract: To smooth the channels for the commercialization of scientific and technological achievements and convert these achievements into real productive forces, the effective support of fiscal policies is required. The commercialization of scientific and technological achievements is characterized by large capital requirements, long commercialization cycles, complex property rights relations, and high commercialization risks. Market entities such as enterprises often find it difficult to independently bear the huge capital investment and risks involved in the commercialization of scientific and technological achievements, which results in certain constraints on the commercialization of these achievements under the market mechanism. This requires the government to formulate specific fiscal and scientific and technological policies and establish a service platform that connects the supply and demand of technological elements for the transformation of scientific and technological achievements. It should be noted that the effectiveness of fiscal and technological policies is not solely achieved by increasing financial investments. It also requires a systematic examination of the complex characteristics exhibited during the specific implementation of these policies, so that flexible policy formulation and implementation can effectively promote the commercialization of scientific and technological achievements. From the perspective of policy implementation, this paper explores the implementation characteristics of policies from the aspects of implementation intensity, policy orientation, and policy stability, and further constructs a theoretical framework for analyzing the impact of fiscal science and technology policy implementation characteristics on the commercialization of scientific and technological achievements. Moreover, it constructs a panel data sample covering 174 Chinese cities from 2017 to 2021, and empirically examines the effect of implementation characteristics of fiscal science and technology policies. The research indicates that the government's strengthening of the implementation intensity of fiscal science and technology policies is conducive to promoting the commercialization of scientific and technological achievements. When the policy is highly targeted and the commercialization of scientific and technological achievements is taken as the goal of policy implementation, it helps promote the construction of services and realize the agglomeration of innovation resources, thus effectively promoting the commercialization of scientific and technological achievements. When the policy is relatively stable and provides a continuous and stable policy environment for market entities, it helps to enhance the expectations of market entities, and then promotes the commercialization of regional scientific and technological achievements more effectively. The analysis of the effects based on different market conditions shows that when a region has a relatively strong foundation for scientific and technological innovation, strengthening the implementation of fiscal science and technology policies can promote the commercialization of scientific and technological achievements more significantly. When the regional technology market is more active and there is a sufficient demand for technological innovation and commercialization, the promoting effect of the implementation intensity of fiscal science and technology policies on the commercialization of scientific and technological achievements will be more evident. The research can provide theoretical support for an in-depth understanding of the implementation characteristics of fiscal science and technology policies and their effect on the commercialization of scientific and technological achievements. Meanwhile, the research conclusions can provide important insights for the government to flexibly utilize fiscal science and technology policy tools and adjust the implementation approach based on policy objectives, thereby enhancing policy effectiveness.