Abstract: The national green mine pilot policy is recognized as a critical institutional innovation driving the mining industry’s green transition. It is urgent to study how should mining enterprises balance their interests in the face of the challenge of tightening environmental constraints. Grounded in signal theory, panel data from Chinese listed mining firms （2007-2018） are analyzed using a staggered Difference-in-Difference （DID） method to empirically evaluate the policy’s impact on corporate value, its dynamic effects, transmission mechanisms, and the moderating role of corporate social responsibility. Key findings reveal that the policy exerts a short-term suppressive effect on corporate value, attributed to heterogeneous interpretations of regulatory signals across stakeholders. This conclusion withstands robustness checks and endogeneity adjustments. Mechanistic analysis identifies two pathways driving value reduction: heightened R&D expenditures and elevated risk exposure, both amplifying short-term operational costs. However, sustained corporate social responsibility engagement is demonstrated to counteract this suppression by enhancing corporate reputation, offering strategic guidance for balancing short-term costs and long-term gains in green transitions. Spatial heterogeneity analysis highlights divergent regional outcomes: the eastern region exhibits significant value suppression due to environmental liability constraints, the central region benefits from policy dividends through green mine clustering, while the western region shows negligible impacts owing to ecological fragility. Mineral-specific heterogeneity analysis demonstrates that ferrous and non-ferrous metal enterprises are subjected to significant short-term suppressive effects under the policy, primarily attributed to rising environmental compliance costs and delayed returns on green investments. In contrast, coal enterprises are observed to exhibit positive effects due to policy incentives and green certification premiums. Meanwhile, oil and gas extraction sectors are characterized by limited marginal effects of policy interventions, driven by their lower environmental externalities. Based on these insights, recommendations are proposed to optimize resource allocation, leverage policy incentives, strengthen CSR practices, and adapt green mine strategies flexibly, thereby facilitating sustainable transformation in the mining enterprise.