Environmental risks established as elevated temperatures, altered precipitation patterns, and extreme weather events, hence generating systemic risks to corporate investment operations. The study analyzes the impact of environmental risk on the expenditures of non-financial firms listed on Borsa Istanbul from 2000 to 2024. The composite environmental risk index is formulated by principal component analysis, incorporating indications of temperature, precipitation, and disasters. The results have derived from baseline regressions, two-stage least squares estimation, mediating effect models, and several robustness checks, reveal a strong negative relationship between environmental risk and corporate investment, attributed to heightened financial restrictions. The effect is most acutely experienced by state-owned corporations, firms in high-risk industries, and those receiving little government subsidies. The analysis of geographical heterogeneity indicates more pronounced negative impacts in eastern Turkiye, categorized by a highly regulated environment and a probably diminished capacity for the normal operation of financial services. Further, the study indicates that environmental risk diminishes overall investment while augmenting the scope of green investment, hence enhancing investment efficiency. In the face of climate uncertainty, focused policy interventions like environmental risk management, financial system fortification, and selective government subsidies are needed to protect investments.