<p>Balancing the dual objectives of ensuring stable economic growth and promoting the green transformation of economic structure is a crucial issue faced by China’s current stage. This paper examines the effectiveness of Green Finance Pilot Policy from a micro-enterprise perspective. Based on data from Chinese A-share listed companies, the study employs a difference-in-differences (DID) model for empirical analysis. The research finds that the Green Finance Pilot Policy has a significant positive impact on the environmental performance of all enterprises in the pilot zones, particularly demonstrating strong institutional constraint effects on polluting enterprises. Mechanism analysis reveals that the policy improves enterprise environmental performance through two pathways: by increasing external financial constraints on polluting enterprises and by enhancing internal environmental attention within the enterprises. Furthermore, the analysis indicates that the impact of the Green Finance Pilot Policy is stronger on state-owned and small-scale enterprises, exhibiting significant heterogeneity based on listing age and capital intensity. This paper demonstrates the effects of the Green Finance Pilot Policy from a micro-enterprise perspective and analyzes its mechanisms for improving enterprise environmental performance from both internal and external perspectives. It provides empirical evidence and policy implications for further innovative green finance policies and enhancing enterprise environmental performance.</p>