Against the backdrop of vigorously developing a green economy, the role of green finance in promoting corporate green innovation has garnered significant attention from academia. To explore the impact of green finance on corporate green innovation, this study uses a sample of A-share listed companies from Shanghai and Shenzhen between 2013 and 2020. A fixed effects model is employed to examine the effects of green finance on corporate green innovation, as well as the specific roles of R&D investment and financing constraints in this process. The findings indicate that green finance significantly enhances corporate green innovation, with its mechanism operating primarily through increased R&D investment. Additionally, financing constraints negatively moderate the relationship between green finance and corporate green innovation. After conducting tests for endogeneity and robustness, these conclusions remain valid. Furthermore, compared with non-state-owned enterprises and enterprises in the central and western regions, the impact of green finance on green innovation is more pronounced in state-owned enterprises and enterprises in the eastern region.