Abstract: How to improve the leveraging effect of unit R&D subsidies on enterprise R&D investment is a difficult problem in public R&D policy governance. Due to the existence of information asymmetry, the "incentive effect" and "catering effect" coexist in the process of implementing R&D subsidy policy Reviewing the literature, some researches have made some useful explorations on this problem from the perspective of enterprise internal governance and external supervision. However, the existing research has not discussed this issue from the perspective of financial institutions playing the role of supervision and governance. As an important external body supervising corporate behaviors, financial institutions have stronger analytical ability than ordinary investors. In the context of fintech, the information collection and processing ability of financial institutions has been greatly improved. Based on this background, we use the panel data model to test whether fintech can improve the implementation performance of public R&D subsidy policies through public governance mechanisms. It is found that fintech can significantly promote the leveraging effect of R&D subsidies on R&D investment by enhancing corporate information transparency, curbing the tendency of R&D manipulation, and regulating the use of subsidy funds. Through the research on the effects of fintech and R&D subsidy policy, this paper confirms that the development of fintech can help to amplify the effect of fiscal policy implementation, and provides a new idea for the use of fintech to help to improve the allocation efficiency of public resources such as R&D subsidies. According to the research results, we propose that, first, in the future, financial institutions such as banks should be vigorously promoted to develop fintech. By strengthening the information collection and processing ability of financial institutions, the supervisory and governance role of financial institutions on real enterprises should be enhanced, the market operation order should be standardized, and the promoting effect of financial system on the development of real economy should be strengthened. Second, we should vigorously promote the application of digital information technology in the fiscal and financial fields, build an information sharing platform between financial institutions and fiscal departments, and use the power of financial institutions to enable fiscal departments to more accurately understand the situation of enterprises, so as to formulate industrial policies such as R&D subsidies and improve the effectiveness of policies.