["Business Strategy and the Environment, EarlyView. ", "\nABSTRACT\nThe deterioration of biodiversity has become a material financial concern, influencing firm productivity and long‐term value. This study examines the link between biodiversity disclosure and firm value using a sample of firms in the European Union. A composite biodiversity disclosure score is developed to capture the scope and quality of reporting across biodiversity, water, supply chain, pollution, and waste. We employ panel data from 2015 to 2023 to estimate fixed effects regressions with Tobin's Q and EV/EBITDA as valuation proxies. The results show that biodiversity disclosure is positively associated with firm valuation, particularly in biodiversity‐intensive industries and among firms with higher ESG performance. As biodiversity loss and climate change are mutually reinforcing, transparent biodiversity reporting also signals firms' resilience to climate‐related transition and physical risks. These findings suggest that credible biodiversity transparency enhances investor confidence, reduces information asymmetry, and reflects preparedness for both ecological and climate‐related regulatory shifts. Our study contributes to the emerging literature on biodiversity and climate finance by offering a framework for measuring biodiversity disclosure and informing how investors and regulators may incorporate nature‐related information into firm valuation and investment decisions.\n"]