Based on the Environmental Kuznets Curve (EKC) theoretical framework

this study employs panel data from 11 provinces and municipalities in the Yangtze River Basin from 2012 to 2022. We construct a two-way fixed effects model incorporating green finance variables and their interaction terms to empirically examine the impact mechanism of green finance on environmental pollution

represented by sulfur dioxide (SO₂) emissions. The analysis includes regional comparisons (upstream

midstream

downstream) and robustness tests. The findings are: (1) A significant inverted U-shaped EKC relationship is confirmed in the upstream and midstream regions of the Yangtze River Basin

but this relationship is not significant in the downstream region. (2) The development of green finance

measured by the proportion of green credit

has a significant inhibitory effect on environmental pollution in the upstream and midstream regions. Through its negative interaction with economic growth

green finance promotes the earlier arrival of the EKC inflection point. However

in the downstream region

the emission reduction effect of green finance is not significant and may even exhibit a "green transition paradox

" potentially due to "greenwashing" or shifts in pollution source structures. (3) Robustness tests

including substituting pollution indicators

considering lagged effects

and comparing model specifications

consistently support the reliability of the core conclusions. The study demonstrates that green finance policies can effectively promote regional green transformation

but their effects are regionally heterogeneous. Policy design should

therefore

emphasize medium-to-long-term financial support

improve evaluation mechanisms

and implement differentiated strategies across regions.