This study examines the impact of environmental performance (EP) on sustainable development capabilities (SDC) in China’s real estate industry, with reducing operating expense ratios (RO) as a mediating variable. Drawing on the Triple Bottom Line framework and a sample of 675 respondents, the study employs Partial Least Squares Structural Equation Modeling (PLS-SEM) to analyze the proposed relationships. Results reveal that EP has both a direct positive effect on SDC and an indirect effect through RO, highlighting the financial-operational mechanism that connects environmental actions to long-term sustainability. The findings offer new theoretical insights into ESG impact pathways and underscore the practical value of integrating environmental strategies with cost-efficiency measures. This research contributes to a deeper understanding of how real estate firms can enhance their sustainability capabilities through targeted environmental initiatives and improved operational performance..