Abstract
This study examines the effect of financial agglomeration on green technology innovation and its spatial spillovers across 27 cities in China's Yangtze River Delta from 2009 to 2023. Financial agglomeration significantly promotes green technology innovation, with heterogeneous effects shaped by local conditions. This positive impact is amplified in cities facing tighter financing constraints and those with stronger human capital infrastructure. In contrast, more stringent environmental regulations weaken the marginal effect of financial agglomeration on innovation. We also found positive spatial spillovers: financial agglomeration in one city promotes green innovation in neighbouring areas. The results highlight the importance of aligning financial development with local institutional and structural conditions. Policymakers should enhance the allocative efficiency of financial clusters, invest in human capital, and improve cross-city coordination to support green innovation diffusion.