This paper applies data of listed Chinese companies from 2000 to 2017 and a time-varying DID model to examine the effect of the National Development Zones (NDZs) and Provincial Development Zones (PDZs) on green innovation. First, it is found that NDZs can significantly boost companies' green-innovation, while PDZs can slightly inhibit the quality of green innovation. These results still apply even after a series of robustness checks. Second, supply chain finance, environmental regulation, and green finance are three mechanisms through which NDZs exert a beneficial influence on green innovation. In contrast, the negative effects of PDZs stem primarily from lax environmental regulations. Finally, heterogeneity analysis shows that the establishment of NDZs has a significant effect on promoting green innovation in non-resource-based urban enterprises, non-state-owned enterprises, and small-scale enterprises.